MS Exchange <==> Debian 1.2 Incompatibility?

[Pete Harlan <harlan@mymenus.com>]

Hi,

When a site running MS Exchange Ver. 4.0.994.63 sends us mail, it gets
stuck(*).  This is true whether we run smail or sendmail.  We're a fresh,
updated Debian 1.2 site.  (We didn't have this trouble when we were a
stale, ancient, Slackware 3.0 site.)  I'm running kernel 2.0.29 with
the pre-2.0.30 patch applied (same behavior with stock .29).

Here are some relevant bits from daemon.log (we're mango):

  Mar 20 16:44:23 mango sendmail[12297]: collect: premature EOM:
  Connection reset by [207.14.169.10]

  Mar 20 16:44:23 mango sendmail[12297]: QAA12297: SYSERR(root):
  collect: I/O error on connection from [207.14.169.10],
  from=<Thurman@usagl.com>: Connection reset by [207.14.169.10]

  Mar 20 16:44:23 mango sendmail[12297]: QAA12297:
  from=<Thurman@usagl.com>, size=0, class=0, pri=0, nrcpts=1, proto=SMTP,
  relay=[207.14.169.10]

Any ideas?

TIA,

Pete Harlan
pete@mymenus.com

(*) Stuck means that "netstat" shows a connection as ESTABLISHED, and
sendmail is sitting there forever waiting for more.  Eventually they
go away and no mail is delivered.  (When I ran smail, they didn't go
away; I'd reboot and they'd fire up again, a bunch of in.smtpd
processes.)