bounced mail

[marsd]

recently set up mail service for a site that now has problems with bounced mail. not good...
basically have a masqueraded mail hub which relays
by MX and for domain to allow outoffice users to use the mail if they point to it.
I went into the site to look at the problem and saw that
the bounces on their side were not logged. 90% of the mail
would get through, but mail from aol, a small isp locally,
and an .edu domain that they vitally need mail from were
not getting through.
I ran tcpdump for a while to watch for mail from these places, and saw right away that the .edu mail server
would connect and then nothing would happen-no connection nothing,it just dropped without a sound. I thought it had to be a firewall rule but there are none that match.

the machine does sec.dns as well and is minimal:
_____________________________________________________
48 megs RAM ; 200 mhz 586 ; 2.2.14 kernel..
sendmail 8.9.3
______________________________________________________

This site does not have a lot of mail so sendmail is running from inetd..
Any ideas? All i can think to do is run sendmail standalone,
but thought maybe someone has seen this before?

 

[StarTAC]

personally, i haven't seen this before, but u may get better debugging if you run sendmail as its own process...

good luck