Hello,
Thank you all, for replies. After researching deeply on this,
the following steps were performed to resolve this issue:
- Enable same RBL checks on secondary mail server
- Tell SpamAssassin on primary mail server - that secondary MX server
is not ALL_TRUSTED. SA was giving negative points to all messages
from secondary MX.
http://wiki.apache.org/spamassassin/FixingAllTrusted
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