Increasing per-process memory limits?

[njc]

Hello,
 I'm currently using Zope's Plone application which relies heavily on 
python. When uploading large files (>65 megs, possibly higher), the 
python process is bombing out with a 'memory exceeded' error. I'm using 
4.8-STABLE . I've been told that if I increase the amount of available 
memory to the python process that I can resolve this issue. I've 
attempted increasing the max users variable in the kernel to 0, hoping 
it might auto-tune, but that doesn't seem to be working. Am I tweaking 
the wrong area? Where should I be looking?