Cool tip. We do a lot of java-stuff at work (sadly, little Perl) and we have never been able to debug native code and usually resort to fprintf, or writing a command line tool to use the libraries as opposed to Java over JNI. This might help! Just thinking outloud here, but what happens with the Inline modules? I've never used them (I need to!), but I am guessing using Inline ::C to call into a module would pretty much keep debugging the same way? Does Inline::C complicate the Perl debugger?