Problem with Droping user table called DUAL

I am not able to drop a table I created called 'DUAL'. It gives the following error.

SQL> drop table vijay.dual;

ORA-00056: DDL lock on object '910' is already held in an incompatible  mode

Is there any clash with the system table called 'DUAL'? I have this problem even after restarting the database, therefore releasing all the parse locks.

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Vijay Raghavan                     | We can sort things out together.
ROSE group, Dept of Comp Sc        | 
Rensselaer Polytechnic Institute   | Ph:(518)-276-4838