BM 3.7 sp2/NW 6sp2. Using DNS Proxy for internal DNS (no DNS server
GWIA 6.5 static NAT to public IP with appropriate POP3/SMTP exceptions

3Com NBX 100 Ethernet/IP telephony "server" sending SMTP mail

My GWIA works fine on both incoming/outgoing Internet mail/IMAP/POP3.
My problem is that our new telephony system has the ability to email
voice mails as attached WAV files if desired. I cannot bounce it's
off my GWIA, no such configuration option. It wishes to do it's own MX

lookup and send mail directly to addressed mail server. Did a static
to a public IP, added DNS filter exceptions and one SMTP stateful

This works fine for any mail domain except my own! The 3Com log showsthat my mail domain is resolving correctly, but gives me "...socket 25

open error".

Obviously, outside mail servers can telnet to my GWIA port 25 to sendmail, why can't this one?

Look like some type of weird loopback issue. If I could "fake" an MX
record pointing to the private IP address of my GWIA, I'd be OK.
However, the only way I know to manually add a host record to DNS
is adding a HOSTS file entry. I have tried adding an entry
"" with private GWIA IP to BM HOSTS file. This worked as
as I can ping "" and it resolves to GWIA private address.
But when I point the 3Com to BM DNS proxy, I get "cannot resolve". It obviously wants to see a DNS MX record.

I have been given three options

1 - add entry to 3Com HOSTS file - can't, 3Com does not allow access
system HOSTS file.
2 - add secondary MX record to ISP DNS for me with lower priority,
pointing to private ip of GWIA. Unsure of effect on normal Internet
3 - install an internal DNS server with a MX record for
pointing to GWIA private ip.

Thoughts? TIA.
Thomas E. Spafford
Director, IS
Hickok, Inc.