I'm writing this article in English, as the information on GCJ + Antlr3 is quite rare, as of 2009.08.16 http://weblog.hypotheticalabs.com/?p=94 I saw an article from Hypothetical Labs that describes the method to compile antlr-3.0 into native code, but it is a little bit out dated now. I tried to compile more recent version of antlr3 and got it to work. Tested with antlr-3.1.2.jar. You need JUni..