Yep...thats the E53 rear climate option...but as listed in your options above...you don't have the rear heated seats.
The pic below (I just went out to garage to take a snap shot) shows both options. Sorry about the icon screw up...I've only had my X5 since Thursday...and it has been dark everytime Ive looked in the back seat..I couldn't see that the upper icon on the left was that of a "fan". (oops)
