AS/400 SMTP mail problems

Is anyone having problems using their AS/400 to send e-mail where mail to most 
addresses works, but mail to certain addresses consistently fails with somethng 
like:

NOT ABLE TO DELIVER MAIL TO SOME/ALL RECIPIENTS.
REPLY CODES WITH FIRST DIGIT = '4' OR '5' ARE ERROR REPLIES.
ERRORS THAT DO NOT HAVE ERROR REPLY CODES MAY EXIST.

HOST DPS NOT ABLE TO DELIVER MAIL TO FOLLOWING RECIPIENT(S):
   <Soucy@petro-canada.ca>
RETRIES EXHAUSTED WHILE ATTEMPTING TO CONNECT TO REMOTE HOST petro-canada.



Yet you can send e-mail to these addresses from non-AS/400 e-mail systems with 
no problem.




Neil Palmer         DPS Data Processing Services Canada Ltd.
                                             AS/400~~~~~
Thornhill, Ontario,  Canada    ___________          ___  ~     
Phone: (905) 731-9000  x238   |OOOOOOOOOO| ________  o|__||=   
Cell.: (416) 565-1682  x238   |__________|_|______|_|______)   
Fax:   (905) 731-9202          oo      oo   oo  oo   OOOo=o\   
mailto:NeilP@DPSlink.com    ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ 
http://www.DPSlink.com        AS/400  The Ultimate Business Server      


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