Just a point that seems to be overlooked in these discussions: there appears to be an "interlock" of sorts, based on the actions of the pressure sensors in the seats also. For example, if you have the entry system based on the default (driver's door unlock only initially), then there are two conditions that can happen.
Assuming that the entering passenger has his/her spare fob on their person, if the driver approaches his/her door and grabs the handle, it alone unlocks and as long as he then simply stands there without getting in and sitting down, as the passenger approaches and grabs their handle, it will also unlock.
However if, at the point of single driver's having being unlocked, they then proceed to sit down on the seat before the passenger has managed to grab the handle, the action of sitting down immediately locks out the other door's keyless entry even if the passenger has a fob, and to let the passenger in, use has to be made of the manual unlock switch button on the driver's door to unlock the passenger door. This makes sense in relation to anti carhigh-jackingif you think about it.
I've also noticed another behaviour when I'm out on my own though. For example, If I go into a shop having locked the car in the normal way, when I then come back to the car but instead of going to the driver's door first I go to the passenger's (to dump a bag on the seat say...) and unlock that first, when I get back round to the driver's door, I find that it has already unlocked which would imply that opening the passenger door first automatically opens the driver's door anyway! That's how it behaves on mine anyway... I'd be interested to hear about others...
