[Zope] Problem passing parameters to a Python Script

I'm passing some paramters from an HTML form to a python script. I'm having trouble determining exactly which parameter is/isn't being passed to a python script. I get an error message saying "Zope Error" "Resource not found" along with a few troubleshooting suggestions -- but nothing else. Yes, I do know what the form is passing, and yes it does jive with the parameter list. Is something else going on? Is there a way to determine which parameter is causing the problem (i.e., get a more descriptive error message)? TIA, Ron