posible but hate to say that it still should work a year old post would have already gone through 2-4 google pr updates, so why would it still have high pr? The pr in forums is RARELY based on its position its normally based on backlinks from sites talking about that topic.
I mean on inactive forums ya the top articles may have some pr from the top domain but, most forums are actively moving and not many get bumped from 1 year old posts, thought it begs the question wouldnt 10 1+year old posts getting bumped piss off and alert the forum owners/users