Help: Type not accessible

["Mattimus" <mattisgrat@yahoo.ca>]

Ok guys here's the jist of what I have.

package Navs is

    type Nav is tagged
        record
            Position : Integer;
        end record;

    type Navpointer is access all Nav;

    function Getposition (Anav : in Nav) return Integer;
    procedure Setposition (Anav : in out Nav; Anint : in Integer);
end Navs;

with Navs;
use Navs;

with Navinterfaces;
use Navinterfaces;

with Displays;
use Displays;

with Ada.Text_Io;
use Ada.Text_Io;


procedure Main is

    Mynav : aliased Nav;

    Pointer_To_Nav : Navpointer;

 begin

    --create a pointer to the nav to give to the nav interface
    Pointer_To_Nav := Mynav'Access;  <--- THIS LINE WILL NOT COMPILE


It tells me that 'Mynav is not accessible from  access all nav'.
Can someone please help. I have no idea what to do here, or what is causing
it.

Thanks a lot guys.