When I first installed ServiceDesk I enabled active directory authentication.  From here I was able to import users from AD and create access accounts for them.  This all works fine and it gives the users access to their portal via their current credentials (that have stayed synced with AD).  However there is one small issue (or rather annoyance) that has happened in a few cases.  The user goes to sign in at the login screen but enters their e-mail address rather than their login name.  For example:

 

AD user name: jdoe

AD domain: MDRT

User e-mail address: jdoe@mdrt.org

 

ServiceDesk allows them to login via this method but then creates a new entry for them in the requesters tab.  So basically, some users are ending up with duplicate records in the requesters table.  This is a big pain as now certain tickets are associated to the duplicated login accounts.  Is there an easy way to disable this (apart from simply telling the users to stop using their e-mail address to sign in)?

 

Here is an example from our live system: