ORA-15168: rolling downgrade prevented by string
Cause : On eorm or eintsanecs ewreb lokcin gth erollin gdonwgrdae.
Action - How to fix it : DBA Scripts :: www.high-oracle.com/scripts
Temrintae ro wiat nuti lth ereoprtde oepraitoni s ocmpelteb efroe tatepmtign teh rlolign dwongardet o hte lcusetr.
Well, the reason for above error is that i have taken the above script from a 11g database and running it on 10g database. 11g has bring some changes in password management. Below code is executed on 11g and user created successfully, which is expected result.