User gets two accounts when logging in from Web and via email


At our site we use sendmail with the long name feature enabled. This 

means a user that has a username jdoe and a gecos field set to the users
full name say John Doe can have email addressed to either
or also have the LDAP Overlap installed. The problem
is the following,

When a user logs on from the web interface their account gets
automatically created based on their LDAP username and email, where the
email from the LDAP is their The problem is if this
same user sends an email to RT but they have configured their mail
client to use their return email address as as new user
gets created called, now the user has two accounts one
by their username created when they login via the WEB UI and the other
when they send email directly to RT.

How can I avoid this?

Do I have to customize my LoadORCreateByEmail in or is
there another way.