[BlueOnyx:03577] Stupid spam filters

[Colin Jack]

We are seeing an increasing problem with spam filters not reading headers correctly and bouncing mail (Barracuda seem to be particularly bad).

Example:

Our ADSL users use our BX box as an SMTP relay. Let's assume that our server has a global IP of 195.70.x.x and the sender has an IP of 87.120.x.x on their ADSL line.

The barracuda picks up the ADSL IP (87.120.x.x) and bounces it because there is no PTR. The mail had actually come from our server (195.70.x.x) which is set up correctly.

Any way of 'sanitising' our headers to avoid this? 

Thanks

Colin