[Dovecot] imap-login ESTABLISHED client sessions not timed out by server

[J4K]

Good morning everyone,

    I noticed some mobile client connections that I know should have
timed out at least 20 mins ago, yet these are still there.  The device
in question lost its 3G connection and never re-established it.  I know,
because in this case it was my 'phone ;)  Why should the imap-login keep
the copnnection in in EST, when it was dropped ages ago.  I imagine that
the mobile client did not correctly close down the session, but it
should have timed out on the server. 

Any ideas?  Has anyone noticed this afore?

imap-logi  7819       dovecot   10u  IPv4 24069447      0t0  TCP
logout.klunky.co.uk:imaps->m83-178-105-240.cust.tele2.nl:39042 (ESTABLISHED)
imap-logi  7820       dovecot   10u  IPv4 24069443      0t0  TCP
logout.klunky.co.uk:imaps->m83-178-105-240.cust.tele2.nl:52696 (ESTABLISHED)
imap-logi  7821       dovecot   10u  IPv4 24069536      0t0  TCP
logout.klunky.co.uk:imaps->m83-178-105-240.cust.tele2.nl:55341 (ESTABLISHED)
imap-logi  7822       dovecot   10u  IPv4 24069464      0t0  TCP
logout.klunky.co.uk:imaps->m83-178-105-240.cust.tele2.nl:44647 (ESTABLISHED)

Linux fred 2.6.32-cgmemcap-smack #1 SMP Tue Dec 28 14:28:18 CET 2010
x86_64 GNU/Linux
Debian Squeeze.
Dovecot 1.2.15-4

Best regards, s