Pydev has a debugger for python and jython, and I used (until now) the same version for both. However, after doing some optimizations in the debugger (actually about 2-3 releases ago), many things stopped working well on jython, mainly because
frame.f_trace is not working correctly. I've opened a bug report about it at: http://sourceforge.net/tracker/index.php?func=detail&aid=1717775&group_id=12867&atid=112867.
.. I'd take a look at it, but unfortunatelly I won't have time to check that for quite some time, so, if someone at the jython team could take a look at it, it would be great... (that's a blocker for any optimized debugger for jython).