In Quality Center, to rename the Defects module for a specific project, you must add a record to the DATACONST table for that project. This is a backend database operation that overrides the default module name. The REPLACE_TITLE site parameter is not the correct mechanism for per-project module renaming. You cannot change it through the UI alone. Directly changing the BUGS table would corrupt the database structure - DATACONST is the proper metadata table for such customizations.