ORA-19028: Invalid ADT parameter passed to toObject() function
Cause : The object passed as ADT parameter to sys.XMLType.toObject() is not the same type, or a super-type, of the mapped type.
Action - How to fix it : DBA Scripts :: www.high-oracle.com/scripts
Pass an object of the correct type to toObject().
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.