Need Help passing values from Workflow function into stored procedure in Oracle

I have modified an Oracle MSS Workflow for terminations so that it will automatically update the subordinate's manager whenever a manager is terminated. I am struggling with future dated terminations though because whenever I try to pass a date from the workflow function into the stored procedure I'm calling it returns a null. I'm not sure what is going on. I'm passing the person_id with no problem, but can't get a date passed for some reason. No WF error, just passes a null into the procedure variable I have setup.