[imp] function to check if mail server is down

[Chuck Hagenbuch]

Quoting Jie Gao <J.Gao@isu.usyd.edu.au>:

> It would be good to have a function to check if the imap/pop server is
> up at user login and give an appropriate message instead of just saying
> the user has entered a wrong login name or password.

If you can supply a patch that doesn't affect performance adversely, that'd
be great.

-chuck

--
Charles Hagenbuch, <chuck@horde.org>
"After a few minutes the most aromatic and nice smelling Italian coffee 
 will come out of the exhaustpipe." - Our stove-top espresso pot