OK, I have it. So no one else has to go crazy, here it is.

First, you have to create a dialog of some kind. For instance (assuming your Tk root is called 'root'):

Pmw.initialise(root=root)
Pmw.aboutversion('1.0')
Pmw.aboutcopyright('Copyright Montressor 2002.nAll rights reservered')
Pmw.aboutcontact('Yell at me')
app.aboutdialog = Pmw.AboutDialog(root,applicationname="Montressor's Poser Aid")
app.aboutdialog.withdraw()

When you want to display this puppy, you have to do this:

app.aboutdialog.show()
app.aboutdialog.focus_set()

Hope this helps someone

Montressor