When running Server Publisher classes I often get the question if it is possible to edit a task or document category name or even remove a category name once this has been created.
As far as I know this is not possible to do from within the actual QMC however this is possible if you edit the name directly in the QVPR. I am always cautious when touching the QVPR and always make sure I have backed this up before actually making any changes (just look for the Repository tab under Systems > Setup > Management Service and press the Backup button at the bottom of the page). To edit the actual QVPR (XML tables) I use the Power Tool XMLDBViewer. This allows me to connect to the XML table called Category where I can Edit, Delete or even create new Category's directly in the XML table.
Let me know if you have any additional questions about this.