users getting kicked out of webmail

[mikewps]

I have a client that is using one of our plesk servers and recently they are having troubles with users being kicked out of the webmail interface and can't log back in for 30 minutes or longer. And of course by the time they tell the point of contact and the point of contact gets in touch with me, I can long into the user account without issue.

Is there a known/semi-known limit to how many can log into the webmail interface at any given time?
If so, what would we need to upgrade/update?

The server is running Plesk 8.2.1 on CentOS 4.2
Average load 1.73; 1.77; 1.88
Disk space usage 23.9 GB available
Memory usage 1.2 GB available

 

[mikewps]

A slight update, a reboot of the server resolved the issue for a couple of days, but it is doing it again.

Anybody have any thoughts on this?