I had just imported a schema with a lot of procedures and packages, and due to the dependencies, many of them show a status of invalid.
Instead of manually recompiling all the procedures etc, i tried using the command from sqlplus:
execute dbms_utility.compile_schema('SCHEMA_NAME');
However, i got the following error message:

SQL> execute dbms_utility.compile_schema('OLDNAG');
begin dbms_utility.compile_schema('OLDNAG'); end;

ERROR at line 1:
ORA-20000: You have insufficient privileges for an object in this schema.
ORA-06512: at "SYS.DBMS_UTILITY", line 219
ORA-06512: at line 1

What could be the possible reason?
I tried executing this first as user system, then from the same schema after granting it execute privelege on DBMS_UTILITY, but the error message remains the same.