My <java> task is (shortened): <java classname="MosesGenerators" taskname="Service(s)" classpathref="moses.build.classpath" fork="true" failonerror="true"> <arg value="-cacheDir"/> <arg file="${registry.cache.dir}"/> <arg value="-s"/> </java>
Before invoking it I set an empty value to ${registry.cache.dir} unless it is already set: <condition property="registry.cache.dir" value=""> <not><isset property="registry.cache.dir"/></not> </condition> If the value is indeed empty, I would expect that my java class gets three command-line arguments like this: -cacheDir "" -s And, indeed, it does - but only under linux. Under windows the empty argument disappears: -cacheDir -s This may be a native way how Windows deals with such situation, so Ant cannot do much about it. Could anybody conform this, or advise me how to make it work on both OS? Thanks you very much for your help, Martin -- Martin Senger email: [EMAIL PROTECTED] skype: martinsenger consulting for: International Rice Research Institute Biometrics and Bioinformatics Unit DAPO BOX 7777, Metro Manila Philippines, phone: +63-2-580-5600 (ext.2324) --------------------------------------------------------------------- To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]