Change system user password in oracle database 11gR2
The following information existes in my 11g database regarding user 'SYSTEM':
SQL> select name,password,spare4 from user$ where name='SYSTEM';
NAME PASSWORD SPARE4
------------------------------ ------------------------------ ------------------------
SYSTEM D4DF7931AB130E37
Please let me know how to change the system password temporarily and then revert it back to the original value.