It is pretty strange bug in OpenOffice.org (confirmed at least in 1.1.0 and also in upcoming 1.1.1) that thesaurus does not work on the first run of OpenOffice.org before spellchecking is "activated". The full description is available in the issue I reported (#i25299#). Kevin Hendricks confirmed this issue, but it doesn't seem to be connected with thesaurus but with the way Writer works with lingu resources.
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