I have a cert. from Aloha offering two first class seats for the price of one full fare coach (e.g., OAK-OGG is about $1,200). A great deal, but I need four seats for my family.

Is there any way I can get United to match this deal? If so, I'd buy two more coach seats and upgrade them with miles.

I'd appreciate any ideas or experiences you have for this situation.