ORA-16031: parameter string destination string exceeds string character limit
Cause : The value for the specified parameter contained a destination string that is too long.
Action - How to fix it : DBA Scripts :: www.high-oracle.com/scripts
Replace the destination value for the specified parameter with a character string that has a length below the limit specified in the error message.
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.