DXF Export Hidden Layers

I have the following in my code:

     swApp.SetUserPreferenceToggle(SwConst.swUserPreferenceToggle_e.swDXFExportHiddenLayersOn, False)

And I've confirmed it with:

     swApp.GetUserPreferenceToggle(SwConst.swUserPreferenceToggle_e.swDXFExportHiddenLayersOn)

The 'Get' command returns FALSE. However... it's still eporting all layers (including hidden ones).  Is this a bug, or is/are there other setting(s) or toggle(s) I need to set to get hidden layers NOT to export to DXF?

Any help is much appreciated...

Thanks,

Eric

SolidworksApi macros