dba_tab_privs : ORA-00942: table or view does not exist

 hi,

 i have created a function to list granted users on objects, so i need to use dba_tab_privs view.

in sql worksheet it works:

select  distinct grantee from sys.dba_tab_privs;

but in function created with the same user compiler says table or view does not exist

CURSOR cur_grant IS   select  distinct grantee from sys.dba_tab_privs ;

select  distinct grantee into aaa from sys.dba_tab_privs where rownum = 1;    -> the same error

plz reply me the solution.