Something funny with my locking

The locking on my Octy 1.9 tdi ambiente works fine with the key and remotely but when you use the button on the driver's side to lock all doors (the one with a key motif) they all clunck locked but the passenger side cluncks again and unlocks itself, with the rest of the doors remaining locked. This wouldn't normally be a problem only most cabs round here are the same model and colour so it comes in useful when unwanted people try and hop in the back. Anyone with any ideas about what's up?:confused:

Edited 4 November, 200916 yr by photo1983