OLE DB Command and optional parameters for a stored procedure

I'm building an SSIS Package with BIDS 2008R2.  The database that I wish to execute the SP on is SQL Server 2005 with SP4 4.

I have a procedure similar to this:

CREATE PROCEDURE test_insert  
(
@parm1 int 
,@parm2 varchar(50) = NULL 
,@parm3 varchar(50) = NULL 
,@parm4 datetime = NULL 
,@parm5 datetime 
,@parm6 int
)
AS ...

In the Component Properties of the OLE DB Command, I specified the SqlCommand as:

EXEC dbo.test_insert @parm1 = ?, @parm5 = ?, @parm6 = ?

Hit Refresh, and got no errors.

However, when I go to Column Mappings, in the destination columns, I see 3 columns listed.  But they are not the 3 specified (@parm1, @parm5 and @parm6)  Instead, they are the first 3 parameters to the stored procedure @parm1, @parm2, and @parm3.  

All the parameters that were skipped do have a default of NULL assigned.

I'm not sure why I'm not getting the correct list of parameters when mapping.  

Any help greatly appreciated