Firebox X Edge allowing MessageLabs on SMTP

[wcluser]

Hi. We are using MessageLabs to filter our mail. They've provided a list of IPs from which they will send SMTP mail. On our firewall We are supposed to block anything received on SMTP except if sent from one of ML's IPs. We have a WG Firebox X Edge. On the Firewall|Incoming I have created a custom service for protocol tcp port 25. I have set the incoming filter to No Rule, specified the Exchange's IP for Service Host and listed ML's IPs in the From list.

However, spam is still being received that has bypassed ML. So how do I get ONLY this rule to run?

Under Common Services I've left SMTP's filter as Allow and the service host is the Exchange. If I set this filter to Deny NOTHING comes in so the Custom Service isn't used.

Can anyone offer any assistance?

Thanks in advance.

 

[wintek]

Make the built in "SMTP" service as " No rule" and custome service ie port 25 as " ALLOW" and

From: MessageLabs IP
To : Internal Ip of the exchange.