I looked through this script and noticed that it simply updated the members database files, but did nothing to the actual thread files themselves.
It's been my experience with changing usernames that not only the member database files must be fixed, but the following need to be done as well:
[*]search/replace old and new usernames in all forum#.threads files
[*]search/replace old and new username in all thread#.cgi files in all forums
[*]search/replace old and new username in all archiveindex-#.pl, archives.threads and Archive-#/archive#.cgi files (if using archives)
[*]update all threads
[*]update search index
[*]re-run lettercreate.pl (if using memberlist hack)
There's a few other smaller places too, especially if the user is an admin or moderator... it's DEFINATELY not as easy as it looks.
I've been working on automating this process, I'll keep everyone updated on the progress of the project if anyone is interested.
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The BallBusters Network,
http://www.ballbusters.net