mod_python form upload: permission denied sometimes...

[psaffrey at googlemail.com]

I have a mod_python application that takes a POST file upload from a
form. It works fine from my machine, other machines in my office and
my home machine. It does not work from my bosses machine in a
different city - he gets "You don't have permission to access this on
this server".

In the logs, it's returned 403. I also have this error in error.log:

Cannot traverse upload in /pythonapps/wiggle/form/upload because
<function form at 0x7fe7568e31b8> is not a traversable object,
referer: ...

Could this be a network level problem? If so, why does it work from my
home machine but not my bosses machine?? The file to upload is quite
large - 7MB.