Updates to system tables are not permitted. Besides you shouldn't even be considering changing the system tables. Back in SQL 2000 when that was possible, all sorts of messes were made by doing so.
This looks like it should be a continuation of your previous thread on the same topic, so please rather continue the existing thread at http://qa.sqlservercentral.com/Forums/Topic1534372-2799-1.aspx rather than replying here.
Gail Shaw
Microsoft Certified Master: SQL Server, MVP, M.Sc (Comp Sci)
SQL In The Wild: Discussions on DB performance with occasional diversions into recoverability
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