SunOOS4.1.1 and sendmail errror

[William M Gilroy]

I have just upgrade a Sun 4/280 from SunOS 4.0 to SunOS 4.1.1 and
sendmail has broken on the mailhost.   The mailhost is the machine
which I just up graded.  It appears that when sendmail tries to do
a HELO using SMPT it gets a 'host name configuration error'.  This
can be reproduced using mconnect. Any clues on what I a doing wrong?
This only happens when sending mail from the mailhost, all of the
remote systems can connect to the mail host just fine.  Using what
on /usr/lib/sendmail says that it is SendMail version 1.10 of 88/05/05.
The mail host is called pixels, with a domain of att.com. Below is
the output from mconnect:

 mconnect
 connecting to host localhost (127.0.0.1), port 25
 connection open
 220 pixels.att.com Sendmail 4.1/SMI-4.1 ready at Thu, 9 May 91 07:45:31 EDT
 HELO pixels.att.com
 553 pixels.att.com host name configuration error
 HELO pixels
 250 pixels.att.com Hello pixels (localhost), pleased to meet you

The HELO to pixels worked, but not to pixels.att.com.  Sendmail always
tries to connect to pixels.att.com and I get an error.  Does anybody
know what I am doing wrong?   Is my sendmail (which is either invoked
by Mail or by /usr/lib/sendmail -v < /dev/null addr) suppose to be 
connecting to pixels.att.com or should it just connect to pixels?
I have read the manual (feel free to direct me to something I might 
have missed) but it did not shed any light on my problem.   
Any help would be appreciated.

Bill Gilroy
wmg at pixels.att.com
att!pixels!wmg
(908) 949-2566