Merging 2 users with different emails into one


I am running RT 3.6.3. Is there a way to move tickets belonging to
one user to another (with a different email address)? In my setting
(and I guess there are others out there with this same issue), there
are several users who have multiple email addresses from which they
have submitted requests, and now have several logins to look at these
tickets. I want to consolidate these under the user’s primary email
address and inform the user to always use that email to communicate
with RT.

Canonicalized email solution would work fine if I knew before hand
all the email addresses of the user, but not after those tickets have
been created, right?

Thanks for any help,