Monitoring Exchange 2010 - imaps/pop3s alarms

[Shawn Heisey <hobbit (at) elyograg.org>]

I have recently migrated from Exchange 2003 to Exchange 2010.  Several 
times a day, I get alarms for  imaps and pop3s, which are resolved less 
than a minute later.

The graph (http://www.elyograg.org/pop3s.png) shows hourly spikes in 
reponse time.  The alarms are not every hour, but when they do happen, 
they correspond to the spikes.  The email from xymon looks like this.  
Note the "seconds" value, which is extremely low.  Anytime there's an 
alarm, the value is low like this.

----
Service pop3s on server.example.com is not OK : Service unavailable 
(connect timeout)


Seconds: 0.003435
----

There have been no complaints from people who use the service, and 
believe me, I'd hear about it if there was a problem.

The non-SSL versions are not alarming.  I just noticed that the graph 
for pop3 has two entries - pop3 and pop3s.  From what I can tell, it 
checks TLS on the standard test.  The pop3s graph on the pop3 entry 
looks identical to the pop3s graph I've included here, except it's red 
instead of blue.

I suspect that it's related to the throttling policies in Exchange 2010, 
but I don't know what to change.  I don't want to open the default 
throttling policy way up, but I did change the anonymous connection 
limit from 1 to 5.  Has anyone else had this problem and found a way to 
solve it?

Thanks,
Shawn