I've just discovered this and thought other people parsing MediaWiki dump files could also benefit.

Dump files contain a version number in the root element eg: <mediawiki xmlns="http://www.mediawiki.org/xml/export-0.3/" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://www.mediawiki.org/xml/export-0.3/ http://www.mediawiki.org/xml/export-0.3.xsd" version="0.3" xml:lang="vo">

A description of the changes to the format can be found at http://www.mediawiki.org/xml/export-0.4.xsd :

Version 0.2 adds optional basic file upload info support, which is used by our OAI export/import submodule. Version 0.3 adds some site configuration information such as a list of defined namespaces. Version 0.4 adds per-revision delete flags, log exports, discussion threading data, and a per-page redirect flag.

Notice that per-page redirect flags are documented to to begin with version 0.4 dump files. In fact the per-page redirect flag seems to be used from 28 July 2009 and can be found in dump files marked as version 0.3

Given this there are surely other features which occur in versions earlier than documented so it would be wise to allow for this when parsing dump files rather than relying on the version declaration.

Andrew Dunbar (hippietrail)