Idintical from dictionary.comNo. Something cannot be identical to itslef since it is, by definition, itself. jfern cannot hold identical positions to jfern, as he is one being. Marriage cannot be identical to marriage since it is marriage. You need two different things in order to be able to compare them and determine if they are identical or similar.
There could be a giant loophole in saying that two men cohabitating and getting equal treatment to a married couple is dissimilar enough from "the union of one man and one woman" that it is allowed.