Sorry for the confusion Joe.
I'm not using ADFS for writes into the account store, I'm not that advanced yet ;)
I'm using the AD membership provider and using the out of the box .NET controls for that. They are working except the change password just needed that little fix. It really isn't that big of a deal, I was just hoping to find a more elegant solution, like setting that current MembershipUser to the user when I'm checking authentication, instead of setting the name right before I attempt the password change.
Does that make sense now?