New router, No email

[#1]

My old and trusted router died on Wednesday and was replaced with a Netgear DGN1000.  I run an SBS server with SMTP email and am no longer receiving SMTP email.  Other pop accounts work fine.
I have added SMTP, TCP, Port 25 to the inbound allowed side of the firewall.  Have I missed something?

[#2]

Shouldn't it be outbound for sending mail?

[#3]

My email is set for SMTP delivery to me for a domain.  SMTP delivery allows me to manage the email accounts internally.  Basically, anything with @mydomain.co.uk should be shoved through my static IP address to a mail server.  While i can telnet through the port, I am not receiving email.  No response to fingerring the auoturn servers either.
Is it to do with the change of router (probably), or just coincidence that this started on the same day as the bt outage.
The new router blocks everything inbound by default, so I've added smtp on port 25 as a rule, but still nothing.

[#4]

Ah, right. I just saw SMTP and thought "outgoing"...
I'm not sure how the firewall works on that router - do you need to specify the machine on your network which is running the server, or perhaps put it in a DMZ?

[#5]

As I assume that you have set up rules for POP and they work the Port forwarding for SMTP should be the same. You can use http://www.twisted4life.com/tools.php?Menu=smtpcheck
to test SMTP. Just enter the email address and it will do a DNS lookup and connect to the SMTP server.

[#6]

Having opened port 25, scanning the available ports for the desired ip address shows that they are all closed.  I have a block of four addresses that were working perfectly well with the old router.
If i scan the ports on the first of teh ip addresses in the block, port 25 is open.
Something is missing.  Did I create a host name for the ip address before?  why can't i see this option ont he netgear?
May post on the router page too now.