last names displayed in AD Uses & Computers

This has been posted before, but the problem we're having I can't find a solution too... here goes

I ran the ADSI edit to change the way our GAL was formatted and ran the ADModify tool to fix the current users as lastname, firstname. This worked great as the GAL is formatted correctly.

However, AD Users&Comp still shows users as firstname lastname. I've ran the script (successfully) to change all existing users to the lastname, firstname format. The script tells me at the end that users in the target OU were changed, However, they still appear as firstname lastname. The weirdest thing is new users DO appear as lastname, firstname, so now we have an inconsistency in the display name.

Any help would be greatly appreaciated.