troubleshooting Question

Reverse DNS Public IP NAT

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jforville asked on
7 Comments2 Solutions715 ViewsLast Modified:
I am looking for a solution to this problem.  First, my environment:
Exchange Server 2003 SP2: Assigned ISP Public Address
Cisco PIX 506: Outside Interface Assigned ISP Public Address; is set as a one-to-one NAT entry pointed to moy mail server.
MX Record Points to on
Reverse DNS PTR setup by ISP is

My issue is that for certain Mail Servers hosted by AOL and Speakeasy for example, they are rejecting mail from me based on a failed rDNS lookup.  I have confirmed that my mail headers when received by the recipient host show my PIX Outside interface of  I assume that's why their rDNS lookups fail.  Isn't there a way I can resolve this without reconfiguring my network or addressing?
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