Today when I was looking into my facebook wall I found most of my friends was posting the free facebook tshirt. When I ask them they told it was spam. When I try to debug further on the spam i found the problem. They did it in smart way. actually they ask for your name and facebook upload email Id, facebook gives you a unique email Id to upload the status via email address to your facebook account these guys use that upload email Id and update your status with that spam message.
To solve this go to http://facebook.com/mobile and you can see a email Id saying upload via email . Look for find more below the upload email id. Click that and it will open a popup, in that look for refresh the upload email id and click that your unique email Id will change.
DO SHARE YOU FACEBOOK UPLOAD EMAIL ID TO ANYONE
Let me know if you have any issue. If you like the post just like me in facebook