Yup I also get them but don't worry about it. I am sure the one who is sending these will be banned pretty soon.
Just forward spam/crap PM's to any online mods using below given link. http://forums.digitalpoint.com/showgroups.php DON.
I haven't received any unexpected pm yet. even the pm that I expect don't recieve them lol. one day I will become a Shadow Hunter and then I think I will start recieving pm.