RE: IP spoofing I think

[Rantcla]

If you are using Exchange Mail Services 5.5 (SP1) or later you can start by 
filtering incoming mail (SPAM) by going into IMS and selectively rejecting 
incoming messages from the originating host. This is also effective in 
stopping mail loops. Additionally, there are third party software vendors 
that can provide additional software assistance to prevent spam etc.
V/r
Rob Clark