i *am* using a software PHP accelerator, and there's no good reason for anyone to run squirrelmail without one - it dramatically reduces CPU demand.
for those who may be interested, and also unaware of it, there is a freeware php accelerator out there. it works great, and i highly recommend it. figured this was an appropriate followup to my own post.
Paul Theodoropoulos http://www.anastrophe.com