My treo 700p started failing to connect to the internet the same day the ssl cert on my imap account expired. The phone would work perfectly, after a soft reset internet access would work fine for about 5 minutes.At one point I got the following "Error: ppp timeout (0x1231).

While trouble shooting the problem I
1) kept doing soft resets
2) Wiped the palm and internet access worked fine
3) resynced the device to reload all my apps and data. I started getting the hangs again.
4) I wiped the device again just to confirm that it wasn't a hardware issue.
5) fixed my expired cert
6) resynced the device with all my apps and data. Now everything is happy.

So all I can conclude from this is that when versamail syncs to a imap host with an expired ssl cert it kills the ppp stack.

I just wanted to share my experience incase someone else comes across the same problem.