I don't believe there is. the spam tag is being added after it leaves your machine. I am betting it is probably being added on the server level. it is probably the mail server you are trying to send mail through. it would be nice to run a couple tests....
you could rule outlook out of the equation by trying to send out with a different e-mail client. eg. eudora light or outlook express...
netscape communicator.....
see if you get a return then. if you don't then for some reason it's being added at the local machine level......
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I'd rather have a bottle in front of me then a frontal lobotomy.......
My grey matter is turning white, my proof is my grey hair....