I've set up Lucene following the instructions on http://meta.wikimedia.org/wiki/Installing_lucene_search When I get to the indexing stage, I get this error: Unhandled Exception: java.io.IOException: no root element: U+58 at org.mediawiki.importer.XmlDumpReader.readDump () [0x00000] at MediaWiki.Search.SearchTool.SearchTool.ImportDump (System.Stringdumpfile, System.String database) [0x00000] at MediaWiki.Search.SearchTool.SearchTool.Main (System.String[] args) [0x00000] My friend has also set up Lucene on his machine, and he gets the same error. We're both at a loss about what the problem is.