ORA-24809: amount specified will not fit in the lob buffers
Cause : LOB buffering is enabled for the input lob locator so buffering will be used. However, the amount of lob data to read or write is larger than what the lob buffers can hold.
Action - How to fix it : DBA Scripts :: www.high-oracle.com/scripts
Either disable buffering on the input lob locator and reissue the command or pass a smaller amount.
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.