[asdf1234]

How often does this come up? Not too damn often. If two people have pocket pairs, there are precisely 44 boards that will give quads over quads out of a possible 1712304 boards. That's 35672:1 against. Add to that the fact that at least two pocket pairs need to be dealt with all their cards remaining live and you've got something that is incredibly rare. Not to mention that sometimes someone is left with an underpair on the flop and mucks it only to see the board come with their running pair (I've actually done this twice in the last two weeks).

If one person has a pocket pair and the other doesn't, the chances are very minute, slightly less than 2000000:1 against and maybe worse because you said both cards must play. 88 vs. 62 on 88666 wouldn't count, but would sting an awful lot.

So, in conclusion, don't count on it.