I have a 1994 S500 (W140 series chasis). When I put the car in reverse not only do the fender finder antena's come up, but also the trunk partially unlocks and the lifting handle on the trunk pops out. The trunk edge is then about 1/4 above the body metal instead of flush as it usually is. The trunk does not open all the way and seems to still be latched down.

When parked the remote trunk lock works fine, and when you press the button on the trunk to open the trunk, the lid pops up an inch or so and the trunk lifting handle pops out as it should.

When you close the trunk lightly the closing mechanism grabs the trunk lid and gently closes it fully as well as retracting the lifting handle at the same time.

In other words everything appears to work properly EXCEPT that when I place the car in reverse, some gremlin in the trunk opens the lid.