FaceTime and Mail Autofill

We've got four different devices on which we use Facetime (two Macs, an iPod touch and an iPad) and each has been assigned to one of our e-mail addresses.  Some of these are our regular main e-mail addresses that we use for standard e-mail as well as for Facetime.
In order to easily know which devce is assigned which address, I created four contacts with names like "Facetime iPad" and then put in that device's e-mail address.  However, now whenever I send or receive an e-mail at that address it lists the recipient as "Facetime iPad" instead of my name.   The problem is that there are two contacts with the same e-mail address, and Mail is always choosing the Facetime one to autofill. 
I have tried going to the "Previous Recipients" option under the "Window" menu option and deleting the "Facetime iPad" listing, but that name keeps popping up.  I'm going to post this over at the Mail board, but is there any way to either force Mail to use one particular contact, or to create a contact that  Facetime can use that doesn't show up in Mail?


(I meant I posted it on the FaceTime board!  Oops)