2010/8/2 Gerard Meijssen gerard.meijssen@gmail.com:
Hoi, The big problem with upgrading MediaWiki is the upgrading of extensions. It is not documented anywhere if extensions will work with a specific release of MediaWiki. Being able to install extensions is a great thing when you know upfront that the extensions you are interested in will actually work and not crash your installation.
We branch and tag extensions along with versions of MediaWiki, so the code found at http://svn.wikimedia.org/svnroot/mediawiki/tags/REL1_15_5/extensions/ is supposed to work with MW 1.15.5. However, this assumes that the trunk version of each extension worked with the trunk version of MW at the time of the branch point, which is not always the case and is the responsibility of the extension maintainer. Versioned releases can also be downloaded through ExtensionDistributor at mediawiki.org, although ED breaks all the time and we've been getting lots of questions in #mediawiki from people whose wiki broke because they installed the trunk version of ParserFunctions (downloaded through ED) with MediaWiki 1.15.
Roan Kattouwv (Catrope)