How to define an executable to use a package?

Hi there,

New in create package and its usage.  Here is the situation I got:

-  I create a package with a series of procedures in it and compile it without problem.  Let's call it NNN.

-  I need to use it in a concurrent process, so I define an executable with execution method = PL/SQL Stored Procedue

-  However, when I tried to choose executable file name and I couldn't find my package and there is no LOV there.

-  I entered my package name, NNN in executable file name field and system allowed me to save.

-  When I run the concurrent process, it ends with error: PLS-00221: 'NNN' is not a procedure or is undefined