I know some of you guys use postfix.  How do you monitor how many messages
are in the queue?  Outbound connections?  

I need to keep track of this to figure out when stuff sits in my queue too
long, and when I need to add capacity.  Basically, I just need to make sure
the messages go out as fast as they come in.  This is all for stock price
alerts for our clients, so it's very time sensitive.  More than a 10 minute
delay is too much, and the sheer volume of alerts is absolutely crazy.  It's
working fine now, after a switch from qmail to postfix, but the demand is
growing fast.

Jay