Depends - there are 2 types.
Type 1 (not common) - the clutch cable connectes to the engine, and operates an internal clutch. Chain drive to roller. If this type was working and suddenly does not, the internal engine clutch has broken, and will require a complete strip down to repair.
Type 2 - clutch cable goes through the deck and acts on a jockey wheel that tightens the belt when operated. There is a method of adjusting the cable at the handle end. Usually, if the cable is undamages, it means the drive belt has stretched. Replacement required.
phil_saunders(a)bigfoot.com
Phil Saunders, August 2009