Useful extension for An OpenOffice.org – Source language checker for English, German, Polish, Dutch, and other languages. This is a rule-based language checker that will find errors for which a rule is defined in its XML configuration files. Rules for more complicated errors can be written in Java. You can think of LanguageTool as a tool to detect errors that a simple spell checker cannot detect, e.g. mixing up there/their, no/now etc. It can also detect some grammar mistakes. It does not include spell checking.
Update 2009-03-03: Released version 0.9.7. Changes include:

• Small rule updates for Dutch, English, Polish, Russian, and German
• Preliminary support for Romanian (thanks to Ionuţ Păduraru)
• OpenOffice.org integration: fixed a ClassCastException crash that occurred with non-English texts that contain soft-hyphens.
• OpenOffice.org integration: fixed bug with no errors visible in context menu for some languages, for example French.

This version only works with OpenOffice.org 3.0.1 or later and you need to restart OpenOffice.org after installation of this extension