from what i understand when i tried to bypass it that the gps ant sences movement and wont allow you to watch dvd's while in motion.
i was tould by avic411.com to strip the instulation off the ant and put a switch on the inner wire of the ant without disturbing the outside wire...... witch was impossable and didnt work.
check out avic411.com, if there is a way to do it they will know.
edit, just looked there and it doesnt appear they have figured it out yet. There is a thread that is like 12 or 13 pages long with people trying to bypass the z2. Good luck though.