Migrating from Novell NDS to MS AD

Hello everyone! I’m moving from an NDS environment to Active Directory. The problem I have seen so far is that I have many users with the same login name but located different containers under NDS, AD won’t let me create such users as it tells me they already exist. For example, the NDS logins could be: john.humanresources.mycompany, john.finance.mycompany, john.it.mycompany, and each john just logins under novell. Active directory barks right away, even if I put each john in different OUs. Anysolutions (other than changing their login names?). Thanks!