Drop down mask problem

Can anyone please suggest why my drop down menu is being hidden from an externally loaded .swf with a simple mask?

The below link demonstrates how the blue menu is being masked by the grey content area. When you hover over the “Home” link the menu is behind the externally loaded “content” swf. I am trying to display the blue drop down menu over the grey content area but that particular area contains a mask even though my nav/menu reside on a different .swf.

The content.swf file is loaded in the main movie clip using the following code found on the [size=2]**[font=Verdana][color=#003366]Transitions [/color][/font] **[/size][font=Verdana][size=2][color=#003366]Between External SWFs.[/color][/size][/font]