APEX

Hi-
What i'm attempting to do is simple. I have a single HTML page with a region on it called "Buttons" and a single button. The point of the button when pressed is to execute an Oracle stored procedure which performs a query and inserts the result set into a temporary table. Under "Database Manipulation Request/Database Action", i've selected "No Database Action". Under Conditions, i've select Condition Type of "PL/SQL Expression" and placed the name of the procedure in the Expression 1 box. When i run the page, i get the following error:

Invalid PL/SQL expression condition: ORA-06550: line 1, column 34: PLS-00222: no function with name 'PRC_LOAD_TEMP_BULK_DATA' exists in this scope ORA-06550: line 1, column 7: PL/SQL: Statement ignored

The executable is a "procedure" not a function, and i'm guessing that i haven't set up the button properly. How do i properly initiate a database executable from the press of a button?
thanx,
jim.