I haven't run into your situation, or tested the concept, but my first guess would be that the helpbook is throwing an exception of some sort. You might try turning on the debugging options, or try using the command line interpreter to launch the helpbook. When you close it, you should be able to see what exception is being thrown (or what other error might be cropping up) and handle it appropriately in your code...
Not sure if that helps, but I hope so :) Tim -- http://mail.python.org/mailman/listinfo/python-list
