The dealer is probably right. If you have a 2002 model year car, you will not have a radio that supports Aux input. You could upgrade your radio, or you could consider a device like the Intervee II.

__________________
SOLD
2000 E38 750iL Highline Edition, Upgraded with the lastest 2006 X5 Electronics
MKIV Navigation, 16:9 Display, Bluetooth, TV/Video with Backup Camera, Sirius, and Aux Input