port 25 in inside access list

[mudubai04]

Hi,

Just a quick question:

on the inside interface access list on an ASA 5510 (if i am running exchange 2007 on an inside network for instance 192.168.16.0 255.255.255.0) should i have an access list which allows tcp network 192.168.16.0 255.255.255.0 eq smtp or should i just allow host email_server_ip eq smtp?  If i allow entire network do i invite a potential mail relay problem?

Thanks.

[Jitendriya Athavale]

it should be enough if you allow only the traffic from mail server