For me it seems that this is not a Hide Message Bug. I think it is a "normal" UBB bug. Did you test it on a plain UBB installation? Or only on a hacked board?
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.