[mod_python] "Internal Server Error"

Hi all,

Looking through my stats I see some of my users still get an "500
internal server error". Is there any easy way to prevent this?

I've cut down on this already seriously by doing some POST checks (if
the parameter does not exist, reroute to the section's home page instead
of serving an empty page - which causes Apache to serve an "internal
server error").

The current errors are usually from so malformed input I get a crash
(I've to look into that, I know), or more frequently from mistypings in
the URL (http://host/python/main.py/pagename). 

Wouter.