[imp] random timeouts

[Kevin Konowalec]

Using horde 3.0.5, imp 4.0.3, php 5.0.3

We're noticing a number of seemingly random timeouts in our horde/imp  
sessions.  A user will log in and start working and be booted back to  
the login screen without warning.  This happens sometimes several  
times in a short timespan (4-5 times in 10 minutes) and then stop  
happening.  I can't seem to find anything that would be causing the  
problem.

In my php.ini file I have the following set:

session.gc_probability = 1
session.gc_divisor     = 1000
session.gc_maxlifetime = 900

in /horde/config/conf.php I have:

$conf['session']['timeout'] = 0;


Is there something else I could be missing?  At the moment we use  
mySQL for our sessionhandler (we'll be moving to memcached as soon as  
the newest versions of horde and imp are officially released).