I have several users in AD that have their CN like

CN=Ben Litchfield,CN=Users,DC=spam,DC=com and

samAaccountName=bjl1234


I would like to be able to authenticate someone who uses the username bjl1234 and not the 'Ben Litchfield' account. It would also be acceptable if it accepted either 'Ben Litchfield' or 'bjl1234' as the username. Any suggestions?