ORA-12511: TNS:service handler found but it is not accepting connections
Cause : The dispatchers notified the listener that they temporarily do not accept new connections.
Action - How to fix it : DBA Scripts :: www.high-oracle.com/scripts
Attempt the connection again. If error persists, contact the DBA to check the state of the dispatchers and/or ask him to increase the number of dispatchers.
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.