Off the top of my head I thought it was 70000 miles but as already said, I always do it straight away (along with the tensioner) as soon as I get a car that is new to me.........especially if there is no service history.
Actually I don't think I have any official information on when to change oil, oil/filter and cambelt for mk1's and mk2's. Does anyone have the info to hand? What do VW recommend?