Dialogs popup minimized first time under X/fluxbox

The first time I raise a modal dialog in VW7.4 and/or VW7.4.1 under
Linux/x86 the dialog itself and the "parent" window both immediately
minimize.  As a simple example opening an image, selecting File->Exit
causes the Launcher and the "Yes"/"No"/"Cancel" dialogs to both minimize
themselves.  The only time I've seen this is under the fluxbox window
manager.  I've been using fluxbox for years and none of my other dozens
of other X applications have any problems...I've tried various window
manager configuration options but to no avail.  Has anyone else had this
problem or have a guess at a fix?

David