ORA-29853: keyword UNIQUE may not be used in creating domain indexes
Cause : An attempt was made to create a domain index with the UNIQUE attribute.
Action - How to fix it : DBA Scripts :: www.high-oracle.com/scripts
Remove UNIQUE from the CREATE INDEX statement.
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.