postfix relay multiple domains

["veins" <veins@skreel.org>]

I am trying to figure out how to relay mail to a different server depending on
domain of
receipter. I have a gateway and two mail servers, all of them running postfix
as mta.
The gateway should relay mails for domains   A.ORG and B.ORG
mail for A.ORG should be forwarded to server A and mail for B.ORG should be
forwarded
to server B, they live in the same subnet (A = 192.168.2.2 and B =
192.168.2.3), for now
mail sent to A is correctly forwarded while mail for B returns a mail loop
backs to myself
error no matter what. At first sight, it would look like a dns issue to me,
but after lot of
time searching, it appears that dns is working correctly and this seems to be
a postfix
problem. Anyone runs the following configuration ? If yes, could you mail me,
cause I
need this fixed very urgently and I really don't understand what's not
working.

veins
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