Dialog widgets and global mode

I thought this worked, but maybe I am doing something wrong.
AS PERL V5.16-3
tcl V8.5.13
Windows 7 x64

Using Perl and Tkx, trying to create some dialog boxes that use "global"
mode, but that does now seem to work. I can still access other applications
and windows.I have tried using widget::dialog and Dialog from the BWidget
group and tk_widget they all behave the same, "global" just seems to be
ignored and defaults to a "local" behavior.

Anyone have a working example of a simple dialog using "global" modal?

thanks,
gary