[CentOS] sendmail Deferred mail - reason unknown

[Sean Carolan]

"I'm a bit baffled by this problem.  Maybe there's a sendmail guru out
there who can help me out here.  We have some end-users who need to
receive system-generated mail that originates from a java-based
application on our network.  The java app sends the mail through our
sendmail cluster, which then sends the email on to the end-user over
the Internet.  The size of the emails can range from a few kb up
through around 2Mb in size."

I should probably add that each of these emails has an attached file,
which accounts for the large size of the emails.  Also, sorry if my
previous email was sent in HTML format, I think I might have had "rich
text" turned on in Gmail.