nnimap backend gets stuck with ssl

[Konstantin Kletschke <konsti@ku-gbr.de>]

Hi Folks!

I use gnus' nnimap to connect to four imap accounts. While this works
perfect at home to my home imap server this is broken at work over a
dsl connection. When I let emacs idle a minute the imap server
disconnects. 
After that emacs/gnus doesn'T realize that and does no attempt to
reconnect. When I press g in summary buffer it hangs displaying the
hourglass. 

This is with the builtin openssl ssl method or with 

(setq imap-ssl-program "/usr/bin/stunnel -t 110 -c -r %s:%p")

The funny thing is, when I invoke the stunnel command alone, it
connects and returns to prompt after the imap servre is fed up idling.

Is there any help beautyfying this situation? I find some entries in
mail archives or newsgroup but no solution or misleading ones not
matching my situation so I wan't to get to know the actual situation.

This happens with GNU Emacs 22.0.95.1 and its builtin gnus.

Kind Regards, Konsti