Anantsharma is on the right track, as xp_cmdshell is the way to go. Although there is no need to write a C Module when the command shell (Windows -- even back to DOS) provides a command to change the date
EXEC xp_cmdshell 'date 02-01-06' -- This will change the Date on the SQL Server
-- CMD line command date [MM-DD-YY[YY]]
David Lundell
Principal Consultant and Trainer
www.mutuallybeneficial.com