ask dude what date it was manufactured in, and that will tell alot more. unless someone has multiple xbox's to compare the numbers its goign to be really hard to tell anything.
and the date on the back of the xbox might be DD-MM-YYYY or MM-DD-YYYY. i couldnt tell becuase mine was something like 08-10-2005, so it could have either been 8/10/2005 or 10/8/2005. im not sure. but the manufactured date would help more i think.