A method, apparatus and computer instructions for handling exception
vectors by firmware. An exception vector is identified to form an
identified exception vector when control is passed from an operating
system to the firmware. The identified exception vector is saved to form
a saved exception vector. The identified exception vector is then
replaced with a substitute vector; and the saved exception vector is
restored when control is returned to the operating system to form a
restored exception vector. At that point, the restored exception vector
is again used to perform error and debugging processes.