[Exim] Strange delays in connecting

Morning folks
Ever since I've setup our mail hub in our iptables protected DMZ, I've
noticed that there is a significant delay getting a response back from
exim once connected to port 25. Telnetting to port 25 gets a fairly
instantaneous "Connected to" message, but the Mail serer response after
that could be anywhere up to 30 seconds!

Telnetting to port 25 on an identical Exim installation on the local LAN
(ie no firewalling between me and the exim), the connection and response
is instantaneous. What this suggests to me is that exim is trying to do
something in that delay period for the machine behind the firewall,
which the firewall is evidently not allowing. Question is what this is
though.

If anyone could give me any pointers as to what Exim is trying to do
which the firewall could be blocking, please let me know!

Later
Konrad


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* Konrad Michels
* System Administrator
* Surfkitchen Limited
* Abbey House
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* Theale
* RG7 4SA
* United Kingdom
* Tel: +44 118 929 8079
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