552 4.3.1 Message size exceeds fixed maximum message size

[decurion]

NGX R60 (SPLAT)
We use an smtp resource for incoming mail.
The mail server (exchange) is set to accept mail up to 10MB.
Some mails coming in (8MB) are being blocked by the firewall with the message:
<.> failed: 552 4.3.1 Message size exceeds fixed maximum message size

I've set the 'Do not send mail larger than' to 100000KB on the smtp resource.
I've also set it to 100000KB on the 'Don't accept mail larger than' in Advanced-Smtp (properties of the firewall module).

I want to let the mail server deal with the size of incoming mail not the firewall.

Any ideas?

[decurion]

nevermind. it seems the problem is on the exchange server side of things.