Inside lib/python/ZPublisher/HTTPResponse.py there is the following code: def _traceback(self,t,v,tb): tb=self.format_exception(t,v,tb,200) tb=join(tb,'\n') tb=self.quoteHTML(tb) if self.debug_mode: _tbopen, _tbclose = '<PRE>', '</PRE>' else: _tbopen, _tbclose = '<!--', '-->' return "\n%s\n%s\n%s" % (_tbopen, tb, _tbclose) which seems to be a way of switching off traceback dumps in the browser window and have them wind up in an html comment instead. How do I enable this feature. I tried setting Z_DEBUG_MODE to something other that 1 or yes, but it doesn't seem to do anything. If I manually hack the above code to force debug_mode off, then it does what I want. --- Michael Hamilton ( http://home.clear.net.nz/pages/michael.hamilton )