ORA-13703: The snapshot pair [string, string] for database_id string and instance_id string are not found in the current repository.
Cause : The snapshot ids or the database id or the instance id was invalid or the specified snapshots have already been purged.
Action - How to fix it : DBA Scripts :: www.high-oracle.com/scripts
Set valid snapshot ids and retry.
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.