Secret to Ohmaha? 6789s?

[Crimson]

I'm mostly a hold'em player, but sometimes for fun I play a little dealers choice, and a common choice is ohmaha hi/lo. I get 6789s UTG (no one raises anyway...) and fold, asking my amigo if he would have played that hand. He says yes, and he has seen some of the better players raise it. He goes on to say he is suprised to see that I haven't figured something out yet, but wont tell me what.

Can someone explain why this might be a raising hand, and/or what it is I haven't figured out?