On Baptism on Behalf of the Dead

I think the "baptism on behalf of the dead" business is significant especially because it is never cited by Irenaeus as being a specifically "heretical" of the heresies. It is only later Church Fathers who have a problem with the doctine (probably accounting for the reason why the phrase "baptism on behalf of the dead" wasn't changed in the Pauline writings). I think if Irenaeus or Polycarp thought it was heretical Irenaeus would have told us. Lending the possibility that Irenaeus actually accepted the idea ...