When I invite the same collaborator multiple times, I wind up with redundant Person records

(Bug, Investigate , Priority: Critical, Test Status: No automated tests yet , Reported By Justin du Coeur, )
Invites
Summary: Re-inviting the same Person should not create a new Person!
The recipe here is trivial: just invite the same collaborator twice, then look at the Outstanding Invites -- there will be duplicates.
Haven't checked whether this is also true of email invitations, but I would bet it is.