[horde] Active and idle sessions. No difference?

[Arminas]

Hi,

Is there a way to set up length of session for active users? F.e. if I
set $conf['session']['timeout'] = 1800; it counts session length from
the time that user has logged in, but not from user's last activity.
So there is no more difference between idle sessions and active
sessions? Shouldn't it recount when user makes any action?

Thanks,
Arminas