True, and you said it's only happening to some email, correct?
I've had this problem once before, but it was ALL mail, and the problem
was that the permissions on the socket were too restrictive.
Well I don't think that is the case here.

In the MAILER definition, check that sendmail is using 7 as a flag rather
than 8.   I'm away from my docs and my internet connection is painfully
slow, or I'd be more detailed...anyway, good luck!

It has a long set of flags.  Not 8 or 7.... 

Regards

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Oliver Jones » Director » oliver.jones@deeperdesign.com » +64 (21) 41 2238
Deeper Design Limited » +64 (7) 377 3328 » www.deeperdesign.com