I'll concur with the ret spec on all 3 as noted above. As far as general suggestions, I did something like that with my shams up through level 54ish. I plan on doing a 5-pally group when I get back to boxing here in a month or two. I'd probably split up their spells something like this:

Aura: Devotion/retribution/resistX
Seal: Seal of Wisdom on all 3
Judge: Wisdom/Light/Justice

Then I'd just have a basic judge/consecrate spam macro. I'd also use Blessing of Wisdom on all 3 as mana will be the only thing you're gonna ever notice a lack of, IMO. I'd eventually respec one to prot, but I'd not worry about that until you hit 80 and the dual-spec option becomes available.