Control: tag -1 moreinfo
Is this still a problem with newer client and server versions?
Some time ago, I fixed a bug that sounds very similar to your problem - a perl script (x2gosessionlimit) was iterating through all groups. In case of network authentication and shared credentials for a full site (e.g., company), this lead to abysmal delays.
I am hopeful that this also fixed the issue described here.
Mihai