permission on NT4 Domain after upgrade to server 2003

Recently I upgraded NT4 domain to AD server 2003.
I have several NT4 controllers. If I create a new user this user not recognized by NT4 DC. For instance when I try to give permission to this user on NT4 DC after apply I see Account Unknown. On regular NT4 standalone servers I don’t have this problem only on former NT4 DC. Any idea?
Thanks.