Pajero 4wd Activation,

Hello team,
Got a curiosity question.
Went to Hawkes Nest Beach yesterday.
I was stopped at the Lemontree entry letting my tyres down and there where three young blokes in a late model Pajero doing the same thing just in front of me.

They where finished first and headed off along the access track. The Pajero went about 15 metres and dropped down to the rear axle, bogged.

I finished letting my tyres down and they where stll mucking around digging the hole they where in deeper.

I wandered over and asked them what was happening. No drive to the front axle was the answer. (Figured I may as well have a chat as the track was totally blocked)

I asked the usual questions, free wheeling hubs, stubby lever etc. I know their tyre pressures had been seen to as I watched them do that part.

Anyway's, I snigged them back to the carpark and they packed and left mumbling and muttering in obscene languages.

About an hour or two later they drove along the beach past me without any troubles. I never got to ask them what the trouble really was. It couldn't have been much more than the nut on the steering wheel by the time it took to fix!!

According to the young bloke the Pajero is part time 4wd without free wheeling hubs. This just plain didn't sound right to me, but I know nothing about Pajero's.
It had factory alloy wheels all round and the centre of the front rims looked solid to me!

Don't ask me what model the Pajero was, they're like cans of coke to me, they all look the same.

My question is how exactly does the 4wd system on a lateish model Pajero work?
I've absolutely no experience with them, mine is with part time systems on vehicles of the Land persuasion, be it Rover or Cruiser.

Thanks,
Geoff.