[Mimedefang] Tuning for taking mail from qmail - practically denial of service

[Alton Yu]

As some of your probably know, qmail sends a lot of mail at a time and does
not do connection caching, so it'll just hit the box with 15 or so mails at
a time if the mail is destined for that specific host.

My mail server seems to keep running out of slaves every time the sender
does a queue run and 1/2 of it doesn't finish, so it'll just take my box out
momentarily for 5 minutes at a time.

Does anyone have some good tuning tips?

Thanks!