RE: How to: Change Message-ID header.

> I noticed that some Spam filters seem to pick up on the 'blat' 
> portion of the message-id. Is there any way to supply a custom 
> header?

Have a look at the "Miscellaneous RFC header switches" section in the
syntax.txt file from the blat zip file. It looks as if you can do more or
less whatever you like to the message header with the switches available
there.

-- 
Regards
       John