Oh, that explains everything then. Shiites definitely have a different burial method than the Sunnis (the sect I am most familiar with).
McDragon: I think you are referring to Marjas (Shiite scholars), not Imams. There is only one "set" or rules for the sect, it's just that Marjas differ in the specifics and fine details of those rules. The general burial method should be the same for all of them. Shiites only use Marjas as a reference.