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@@ -1,293 +1,934 @@
-
-Introduction
-
-
-Overview
-
-
-The Zebra system is a fielded free-text indexing and retrieval engine with a
-Z39.50 frontend. You can use any commercial or freeware Z39.50 client
-to access data stored in Zebra.
-
-
-
-The Zebra server is our first step towards the development of a fully
-configurable, open information system. Eventually, it will be paired
-off with a powerful Z39.50 client to support complex information
-management tasks within almost any application domain. We're making
-the server available now because it's no fun to be in the open
-information retrieval business all by yourself. We want to allow
-people with interesting data to make their things
-available in interesting ways, without having to start out
-by implementing yet another protocol stack from scratch.
-
-
-
-This document is an introduction to the Zebra system. It will tell you
-how to compile the software, and how to prepare your first database.
-It also explains how the server can be configured to give you the
-functionality that you need.
-
-
-
-If you find the software interesting, you should join the support
-mailing-list by sending email to zebra-request@indexdata.dk.
-
-
-
-
-
-Features
-
-
-This is a list of some of the most important features of the
-system.
-
-
-
-
-
-
-
-
-Supports updating - records can be added and deleted without
-rebuilding the index from scratch.
-The update procedure is tolerant to crashes or hard interrupts
-during register updating - registers can be reconstructed following a crash.
-Registers can be safely updated even while users are accessing the server.
-
-
-
-
-
-
-Supports large databases - files for indices, etc. can be
-automatically partitioned over multiple disks.
-
-
-
-
-
-
-Supports arbitrarily complex records - base input format is an
-SGML-like syntax which allows nested (structured) data elements, as
-well as variant forms of data.
-
-
-
-
-
-
-Supports random storage formats. A system of input filters driven by
-regular expressions allows you to easily process most ASCII-based
-data formats. SGML, ISO2709 (MARC), and raw text are also supported.
-
-
-
-
-
-
-Supports boolean queries as well as relevance-ranking (free-text)
-searching. Right truncation and masking in terms are supported, as
-well as full regular expressions.
-
-
-
-
-
-
-Supports multiple concrete syntaxes
-for record exchange (depending on the configuration): GRS-1, SUTRS,
-ISO2709 (*MARC). Records can be mapped between record syntaxes and
-schema on the fly.
-
-
-
-
-
-
-Supports approximate matching in registers (ie. spelling mistakes,
-etc).
-
-
-
-
-
-
-
-
-
-Protocol support:
-
-
-
-
-
-
-
-
-Protocol facilities: Init, Search, Retrieve, Browse and Sort.
-
-
-
-
-
-
-Piggy-backed presents are honored in the search-request.
-
-
-
-
-
-
-Named result sets are supported.
-
-
-
-
-
-
-Easily configured to support different application profiles, with
-tables for attribute sets, tag sets, and abstract syntaxes.
-Additional tables control facilities such as element mappings to
-different schema (eg., GILS-to-USMARC).
-
-
-
-
-
-
-Complex composition specifications using Espec-1 are partially
-supported (simple element requests only).
-
-
-
-
-
-
-Element Set Names are defined using the Espec-1 capability of the
-system, and are given in configuration files as simple element
-requests (and possibly variant requests).
-
-
-
-
-
-
-Some variant support (not fully implemented yet).
-
-
-
-
-
-
-Using the YAZ toolkit for the protocol implementation, the
-server can utilise a plug-in XTI/mOSI implementation (not included) to
-provide SR services over an OSI stack, as well as Z39.50 over TCP/IP.
-
-
-
-
-
-
-Zebra runs on most Unix-like systems as well as Windows NT - a binary
-distribution for Windows NT is forthcoming - so far, the installation
-requires MSVC++ to compile the system (we use version 5.0).
-
-
-
-
-
-
-
-
-
-
-
-Future Work
-
-
-This is a beta-release of the software, to allow you to look at
-it - try it out, and assess whether it can be of use to you.
-
-
-
-These are some of the plans that we have for the software in the near
-and far future, approximately ordered after their relative importance.
-Items marked with an
-asterisk will be implemented before the
-last beta release.
-
-
-
-
-
-
-
-
-*Complete the support for variants.
-
-
-
-
-
-
-*Finalize the data element include facility
-to support multimedia data elements in records.
-
-
-
-
-
-
-Add more sophisticated relevance ranking mechanisms. Add support for soundex
-and stemming. Add relevance feedback support.
-
-
-
-
-
-
-Complete EXPLAIN support.
-
-
-
-
-
-
-Add support for very large records by implementing segmentation and/or
-variant pieces.
-
-
-
-
-
-
-Support the Item Update extended service of the protocol.
-
-
-
-
-
-
-We want to add a management system that allows you to
-control your databases and configuration tables from a graphical
-interface. We'll probably use Tcl/Tk to stay platform-independent.
-
-
-
-
-
-
-
-
-
-Programmers thrive on user feedback. If you are interested in a facility that
-you don't see mentioned here, or if there's something you think we
-could do better, please drop us a mail. If you think it's all really
-neat, you're welcome to drop us a line saying that, too. You'll find
-contact info at the end of this file.
-
-
-
-
+
+ Introduction
+
+
+ Overview
+
+ &zebra; is a free, fast, friendly information management system. It can
+ index records in &acro.xml;/&acro.sgml;, &acro.marc;, e-mail archives and many other
+ formats, and quickly find them using a combination of boolean
+ searching and relevance ranking. Search-and-retrieve applications can
+ be written using &acro.api;s in a wide variety of languages, communicating
+ with the &zebra; server using industry-standard information-retrieval
+ protocols or web services.
+
+
+ &zebra; is licensed Open Source, and can be
+ deployed by anyone for any purpose without license fees. The C source
+ code is open to anybody to read and change under the GPL license.
+
+
+ &zebra; is a networked component which acts as a
+ reliable &acro.z3950; server
+ for both record/document search, presentation, insert, update and
+ delete operations. In addition, it understands the &acro.sru; family of
+ webservices, which exist in &acro.rest; &acro.get;/&acro.post; and truly
+ &acro.soap; flavors.
+
+
+ &zebra; is available as MS Windows 2003 Server (32 bit) self-extracting
+ package as well as GNU/Debian Linux (32 bit and 64 bit) precompiled
+ packages. It has been deployed successfully on other Unix systems,
+ including Sun Sparc, HP Unix, and many variants of Linux and BSD
+ based systems.
+
+
+ http://www.indexdata.com/zebra/
+ http://ftp.indexdata.dk/pub/zebra/win32/
+ http://ftp.indexdata.dk/pub/zebra/debian/
+
+
+
+ &zebra;
+ is a high-performance, general-purpose structured text
+ indexing and retrieval engine. It reads records in a
+ variety of input formats (e.g. email, &acro.xml;, &acro.marc;) and provides access
+ to them through a powerful combination of boolean search
+ expressions and relevance-ranked free-text queries.
+
+
+
+ &zebra; supports large databases (tens of millions of records,
+ tens of gigabytes of data). It allows safe, incremental
+ database updates on live systems. Because &zebra; supports
+ the industry-standard information retrieval protocol, &acro.z3950;,
+ you can search &zebra; databases using an enormous variety of
+ programs and toolkits, both commercial and free, which understand
+ this protocol. Application libraries are available to allow
+ bespoke clients to be written in Perl, C, C++, Java, Tcl, Visual
+ Basic, Python, &acro.php; and more - see the
+ &acro.zoom; web site
+ for more information on some of these client toolkits.
+
+
+
+ This document is an introduction to the &zebra; system. It explains
+ how to compile the software, how to prepare your first database,
+ and how to configure the server to give you the
+ functionality that you need.
+
+
+
+
+ &zebra; Features Overview
+
+
+ &zebra; Document Model
+
+
+ &zebra; document model
+
+
+
+
+
+
+
+ Feature
+ Availability
+ Notes
+ Reference
+
+
+
+
+ Complex semi-structured Documents
+ &acro.xml; and &acro.grs1; Documents
+ Both &acro.xml; and &acro.grs1; documents exhibit a &acro.dom; like internal
+ representation allowing for complex indexing and display rules
+ and
+
+
+
+ Input document formats
+ &acro.xml;, &acro.sgml;, Text, ISO2709 (&acro.marc;)
+
+ A system of input filters driven by
+ regular expressions allows most ASCII-based
+ data formats to be easily processed.
+ &acro.sgml;, &acro.xml;, ISO2709 (&acro.marc;), and raw text are also
+ supported.
+
+
+
+ Document storage
+ Index-only, Key storage, Document storage
+ Data can be, and usually is, imported
+ into &zebra;'s own storage, but &zebra; can also refer to
+ external files, building and maintaining indexes of "live"
+ collections.
+
+
+
+
+
+
+
+
+
+ &zebra; Search Features
+
+
+ &zebra; search functionality
+
+
+
+
+
+
+
+ Feature
+ Availability
+ Notes
+ Reference
+
+
+
+
+ Query languages
+ &acro.cql; and &acro.rpn;/&acro.pqf;
+ The type-1 Reverse Polish Notation (&acro.rpn;)
+ and its textual representation Prefix Query Format (&acro.pqf;) are
+ supported. The Common Query Language (&acro.cql;) can be configured as
+ a mapping from &acro.cql; to &acro.rpn;/&acro.pqf;
+ and
+
+
+
+ Complex boolean query tree
+ &acro.cql; and &acro.rpn;/&acro.pqf;
+ Both &acro.cql; and &acro.rpn;/&acro.pqf; allow atomic query parts (&acro.apt;) to
+ be combined into complex boolean query trees
+
+
+
+ Field search
+ user defined
+ Atomic query parts (&acro.apt;) are either general, or
+ directed at user-specified document fields
+
+ ,
+ ,
+ , and
+
+
+
+ Data normalization
+ user defined
+ Data normalization, text tokenization and character
+ mappings can be applied during indexing and searching
+
+
+
+ Predefined field types
+ user defined
+ Data fields can be indexed as phrase, as into word
+ tokenized text, as numeric values, URLs, dates, and raw binary
+ data.
+ and
+
+
+
+
+ Regular expression matching
+ available
+ Full regular expression matching and "approximate
+ matching" (e.g. spelling mistake corrections) are handled.
+
+
+
+ Term truncation
+ left, right, left-and-right
+ The truncation attribute specifies whether variations of
+ one or more characters are allowed between search term and hit
+ terms, or not. Using non-default truncation attributes will
+ broaden the document hit set of a search query.
+
+
+
+ Fuzzy searches
+ Spelling correction
+ In addition, fuzzy searches are implemented, where one
+ spelling mistake in search terms is matched
+
+
+
+
+
+
+
+
+ &zebra; Index Scanning
+
+
+ &zebra; index scanning
+
+
+
+
+
+
+
+ Feature
+ Availability
+ Notes
+ Reference
+
+
+
+
+ Scan
+ term suggestions
+ Scan on a given named index returns all the
+ indexed terms in lexicographical order near the given start
+ term. This can be used to create drop-down menus and search
+ suggestions.
+ and
+
+
+
+
+ Facetted browsing
+ available
+ Zebra 2.1 and allows retrieval of facets for
+ a result set.
+
+
+
+
+ Drill-down or refine-search
+ partially
+ scanning in result sets can be used to implement
+ drill-down in search clients
+
+
+
+
+
+
+
+
+ &zebra; Document Presentation
+
+
+ &zebra; document presentation
+
+
+
+
+
+
+
+ Feature
+ Availability
+ Notes
+ Reference
+
+
+
+
+ Hit count
+ yes
+ Search results include at any time the total hit count of a given
+ query, either exact computed, or approximative, in case that the
+ hit count exceeds a possible pre-defined hit set truncation
+ level.
+
+ and
+
+
+
+
+ Paged result sets
+ yes
+ Paging of search requests and present/display request
+ can return any successive number of records from any start
+ position in the hit set, i.e. it is trivial to provide search
+ results in successive pages of any size.
+
+
+
+ &acro.xml; document transformations
+ &acro.xslt; based
+ Record presentation can be performed in many
+ pre-defined &acro.xml; data
+ formats, where the original &acro.xml; records are on-the-fly transformed
+ through any preconfigured &acro.xslt; transformation. It is therefore
+ trivial to present records in short/full &acro.xml; views, transforming to
+ RSS, Dublin Core, or other &acro.xml; based data formats, or transform
+ records to XHTML snippets ready for inserting in XHTML pages.
+
+
+
+
+ Binary record transformations
+ &acro.marc;, &acro.usmarc;, &acro.marc21; and &acro.marcxml;
+ post-filter record transformations
+
+
+
+ Record Syntaxes
+
+ Multiple record syntaxes
+ for data retrieval: &acro.grs1;, &acro.sutrs;,
+ &acro.xml;, ISO2709 (&acro.marc;), etc. Records can be mapped between
+ record syntaxes and schemas on the fly.
+
+
+
+ &zebra; internal metadata
+ yes
+ &zebra; internal document metadata can be fetched in
+ &acro.sutrs; and &acro.xml; record syntaxes. Those are useful in client
+ applications.
+
+
+
+ &zebra; internal raw record data
+ yes
+ &zebra; internal raw, binary record data can be fetched in
+ &acro.sutrs; and &acro.xml; record syntaxes, leveraging %zebra; to a
+ binary storage system
+
+
+
+ &zebra; internal record field data
+ yes
+ &zebra; internal record field data can be fetched in
+ &acro.sutrs; and &acro.xml; record syntaxes. This makes very fast minimal
+ record data displays possible.
+
+
+
+
+
+
+
+
+ &zebra; Sorting and Ranking
+
+
+ &zebra; sorting and ranking
+
+
+
+
+
+
+
+ Feature
+ Availability
+ Notes
+ Reference
+
+
+
+
+ Sort
+ numeric, lexicographic
+ Sorting on the basis of alpha-numeric and numeric data
+ is supported. Alphanumeric sorts can be configured for
+ different data encodings and locales for European languages.
+ and
+
+
+
+ Combined sorting
+ yes
+ Sorting on the basis of combined sorts  e.g. combinations of
+ ascending/descending sorts of lexicographical/numeric/date field data
+ is supported
+
+
+
+ Relevance ranking
+ TF-IDF like
+ Relevance-ranking of free-text queries is supported
+ using a TF-IDF like algorithm.
+
+
+
+ Static pre-ranking
+ yes
+ Enables pre-index time ranking of documents where hit
+ lists are ordered first by ascending static rank, then by
+ ascending document ID.
+
+
+
+
+
+
+
+
+
+ &zebra; Live Updates
+
+
+
+ &zebra; live updates
+
+
+
+
+
+
+
+ Feature
+ Availability
+ Notes
+ Reference
+
+
+
+
+ Incremental and batch updates
+
+ It is possible to schedule record inserts/updates/deletes in any
+ quantity, from single individual handled records to batch updates
+ in strikes of any size, as well as total re-indexing of all records
+ from file system.
+
+
+
+ Remote updates
+ &acro.z3950; extended services
+ Updates can be performed from remote locations using the
+ &acro.z3950; extended services. Access to extended services can be
+ login-password protected.
+ and
+
+
+
+ Live updates
+ transaction based
+ Data updates are transaction based and can be performed
+ on running &zebra; systems. Full searchability is preserved
+ during life data update due to use of shadow disk areas for
+ update operations. Multiple update transactions at the same
+ time are lined up, to be performed one after each other. Data
+ integrity is preserved.
+
+
+
+
+
+
+
+
+ &zebra; Networked Protocols
+
+
+ &zebra; networked protocols
+
+
+
+
+
+
+
+ Feature
+ Availability
+ Notes
+ Reference
+
+
+
+
+ Fundamental operations
+ &acro.z3950;/&acro.sru; explain,
+ search, scan, and
+ update
+
+
+
+
+ &acro.z3950; protocol support
+ yes
+ Protocol facilities supported are:
+ init, search,
+ present (retrieval),
+ Segmentation (support for very large records),
+ delete, scan
+ (index browsing), sort,
+ close and support for the update
+ Extended Service to add or replace an existing &acro.xml;
+ record. Piggy-backed presents are honored in the search
+ request. Named result sets are supported.
+
+
+
+ Web Service support
+ &acro.sru;
+ The protocol operations explain,
+ searchRetrieve and scan
+ are supported. &acro.cql; to internal
+ query model &acro.rpn;
+ conversion is supported. Extended RPN queries
+ for search/retrieve and scan are supported.
+
+
+
+
+
+
+
+
+ &zebra; Data Size and Scalability
+
+
+ &zebra; data size and scalability
+
+
+
+
+
+
+
+ Feature
+ Availability
+ Notes
+ Reference
+
+
+
+
+ No of records
+ 40-60 million
+
+
+
+
+ Data size
+ 100 GB of record data
+ &zebra; based applications have successfully indexed up
+ to 100 GB of record data
+
+
+
+ Scale out
+ multiple discs
+
+
+
+
+ Performance
+ O(n * log N)
+ &zebra; query speed and performance is affected roughly by
+ O(log N),
+ where N is the total database size, and by
+ O(n), where n is the
+ specific query hit set size.
+
+
+
+ Average search times
+
+ Even on very large size databases hit rates of 20 queries per
+ seconds with average query answering time of 1 second are possible,
+ provided that the boolean queries are constructed sufficiently
+ precise to result in hit sets of the order of 1000 to 5.000
+ documents.
+
+
+
+ Large databases
+ 64 bit file pointers
+ 64 file pointers assure that register files can extend
+ the 2 GB limit. Logical files can be
+ automatically partitioned over multiple disks, thus allowing for
+ large databases.
+
+
+
+
+
+
+
+
+
+
+
+
+
+ References and &zebra; based Applications
+
+ &zebra; has been deployed in numerous applications, in both the
+ academic and commercial worlds, in application domains as diverse
+ as bibliographic catalogues, Geo-spatial information, structured
+ vocabulary browsing, government information locators, civic
+ information systems, environmental observations, museum information
+ and web indexes.
+
+
+ Notable applications include the following:
+
+
+
+
+ Koha free open-source ILS
+
+ Koha is a full-featured
+ open-source ILS, initially developed in
+ New Zealand by Katipo Communications Ltd, and first deployed in
+ January of 2000 for Horowhenua Library Trust. It is currently
+ maintained by a team of software providers and library technology
+ staff from around the globe.
+
+
+ LibLime,
+ a company that is marketing and supporting Koha, adds in
+ the new release of Koha 3.0 the &zebra;
+ database server to drive its bibliographic database.
+
+
+ In early 2005, the Koha project development team began looking at
+ ways to improve &acro.marc; support and overcome scalability limitations
+ in the Koha 2.x series. After extensive evaluations of the best
+ of the Open Source textual database engines - including MySQL
+ full-text searching, PostgreSQL, Lucene and Plucene - the team
+ selected &zebra;.
+
+
+ "&zebra; completely eliminates scalability limitations, because it
+ can support tens of millions of records." explained Joshua
+ Ferraro, LibLime's Technology President and Koha's Project
+ Release Manager. "Our performance tests showed search results in
+ under a second for databases with over 5 million records on a
+ modest i386 900Mhz test server."
+
+
+ "&zebra; also includes support for true boolean search expressions
+ and relevance-ranked free-text queries, both of which the Koha
+ 2.x series lack. &zebra; also supports incremental and safe
+ database updates, which allow on-the-fly record
+ management. Finally, since &zebra; has at its heart the &acro.z3950;
+ protocol, it greatly improves Koha's support for that critical
+ library standard."
+
+
+ Although the bibliographic database will be moved to &zebra;, Koha
+ 3.0 will continue to use a relational SQL-based database design
+ for the 'factual' database. "Relational database managers have
+ their strengths, in spite of their inability to handle large
+ numbers of bibliographic records efficiently," summed up Ferraro,
+ "We're taking the best from both worlds in our redesigned Koha
+ 3.0.
+
+
+ See also LibLime's newsletter article
+
+ Koha Earns its Stripes.
+
+
+
+
+
+ Kete Open Source Digital Library and Archiving software
+
+ Kete is a digital object
+ management repository, initially developed in
+ New Zealand. Initial development has
+ been a partnership between the Horowhenua Library Trust and
+ Katipo Communications Ltd. funded as part of the Community
+ Partnership Fund in 2006.
+ Kete is purpose built
+ software to enable communities to build their own digital
+ libraries, archives and repositories.
+
+
+ It is based on Ruby-on-Rails and MySQL, and integrates the &zebra; server
+ and the &yaz; toolkit for indexing and retrieval of it's content.
+ Zebra is run as separate computer process from the Kete
+ application.
+ See
+ how Kete manages
+ Zebra.
+
+
+ Why does Kete wants to use Zebra?? Speed, Scalability and easy
+ integration with Koha. Read their
+ detailed
+ reasoning here.
+
+
+
+
+ ReIndex.Net web based ILS
+
+ Reindex.net
+ is a netbased library service offering all
+ traditional functions on a very high level plus many new
+ services. Reindex.net is a comprehensive and powerful WEB system
+ based on standards such as &acro.xml; and &acro.z3950;.
+ updates. Reindex supports &acro.marc21;, dan&acro.marc; eller Dublin Core with
+ UTF8-encoding.
+
+
+ Reindex.net runs on GNU/Debian Linux with &zebra; and Simpleserver
+ from Index
+ Data for bibliographic data. The relational database system
+ Sybase 9 &acro.xml; is used for
+ administrative data.
+ Internally &acro.marcxml; is used for bibliographical records. Update
+ utilizes &acro.z3950; extended services.
+
+
+
+
+ DADS - the DTV Article Database
+ Service
+
+ DADS is a huge database of more than ten million records, totalling
+ over ten gigabytes of data. The records are metadata about academic
+ journal articles, primarily scientific; about 10% of these
+ metadata records link to the full text of the articles they
+ describe, a body of about a terabyte of information (although the
+ full text is not indexed.)
+
+
+ It allows students and researchers at DTU (Danmarks Tekniske
+ Universitet, the Technical College of Denmark) to find and order
+ articles from multiple databases in a single query. The database
+ contains literature on all engineering subjects. It's available
+ on-line through a web gateway, though currently only to registered
+ users.
+
+
+ More information can be found at
+ and
+
+
+
+
+
+ ULS (Union List of Serials)
+
+ The M25 Systems Team
+ has created a union catalogue for the periodicals of the
+ twenty-one constituent libraries of the University of London and
+ the University of Westminster
+ ().
+ They have achieved this using an
+ unusual architecture, which they describe as a
+ ``non-distributed virtual union catalogue''.
+
+
+ The member libraries send in data files representing their
+ periodicals, including both brief bibliographic data and summary
+ holdings. Then 21 individual &acro.z3950; targets are created, each
+ using &zebra;, and all mounted on the single hardware server.
+ The live service provides a web gateway allowing &acro.z3950; searching
+ of all of the targets or a selection of them. &zebra;'s small
+ footprint allows a relatively modest system to comfortably host
+ the 21 servers.
+
+
+ More information can be found at
+
+
+
+
+
+ Various web indexes
+
+ &zebra; has been used by a variety of institutions to construct
+ indexes of large web sites, typically in the region of tens of
+ millions of pages. In this role, it functions somewhat similarly
+ to the engine of Google or AltaVista, but for a selected intranet
+ or a subset of the whole Web.
+
+
+ For example, Liverpool University's web-search facility (see on
+ the home page at
+
+ and many sub-pages) works by relevance-searching a &zebra; database
+ which is populated by the Harvest-NG web-crawling software.
+
+
+ For more information on Liverpool university's intranet search
+ architecture, contact John Gilbertson
+ jgilbert@liverpool.ac.uk
+
+
+ Kang-Jin Lee
+ has recently modified the Harvest web indexer to use &zebra; as
+ its native repository engine. His comments on the switch over
+ from the old engine are revealing:
+
+
+ The first results after some testing with &zebra; are very
+ promising. The tests were done with around 220,000 SOIF files,
+ which occupies 1.6GB of disk space.
+
+
+ Building the index from scratch takes around one hour with &zebra;
+ where [old-engine] needs around five hours. While [old-engine]
+ blocks search requests when updating its index, &zebra; can still
+ answer search requests.
+ [...]
+ &zebra; supports incremental indexing which will speed up indexing
+ even further.
+
+
+ While the search time of [old-engine] varies from some seconds
+ to some minutes depending how expensive the query is, &zebra;
+ usually takes around one to three seconds, even for expensive
+ queries.
+ [...]
+ &zebra; can search more than 100 times faster than [old-engine]
+ and can process multiple search requests simultaneously
+
+
+ I am very happy to see such nice software available under GPL.
+
+
+
+
+
+
+
+ Support
+
+ You can get support for &zebra; from at least three sources.
+
+
+ First, there's the &zebra; web site at
+ ,
+ which always has the most recent version available for download.
+ If you have a problem with &zebra;, the first thing to do is see
+ whether it's fixed in the current release.
+
+
+ Second, there's the &zebra; mailing list. Its home page at
+
+ includes a complete archive of all messages that have ever been
+ posted on the list. The &zebra; mailing list is used both for
+ announcements from the authors (new
+ releases, bug fixes, etc.) and general discussion. You are welcome
+ to seek support there. Join by filling the form on the list home page.
+
+
+
+