802.1x logoff profile problem

Hi,

I got 802.1x + win2k3 IAS(radius) + linksys WRT54G WPA (radius) to work
using PEAP authentication.
It works fine, except one annoying problem: User profiles are not saved
during logoff due to network problems. (network location no longer
available)
Profile loading during logon is no problem.

It seems that the transition from user credentials to computer credentials
during logoff is rather slow, and happens during the saving of the roaming
profile.
Credential transition during logon also happens (correctly, i can see that
in the ias event logs), but does not cause a connectivity problem as far as
I can see.

I'm using the standard winXP 802.1x.

Does anyone know what to do about it?

thnx
bert