Since many have not run 5.5.1 in a few years I think it very hard to tell you how to do this.
Best thing you can do is upgrade your Infopop members area membership and downloaded the latest greatest UBBThreads and take advantage of many many improvements.
Donate to UBBDev today to help aid in Operational, Server and Script Maintenance, and Development costs.
Please also see our parent organization VNC Web Services if you're in the need of a new UBB.threads Install or Upgrade, Site/Server Migrations, or Security and Coding Services.
