Should there be a way to leave the separator out of a GtkDialog?

[Guy Harris <gharris flashcom net>]

A GtkDialog currently draws a separator between the action area and the
rest of the dialog box; if the new GtkDialog is intended to be more
widely used than the old one

	1) should it still be used only in dialogs where the action
	   buttons are to be separated from the rest of the dialog box
	   by a separator (the file selection, font selection, and color
	   selection dialog boxes in 1.2.7 don't have such a separator)?

	2) should all dialog boxes have such a separator?

	3) should there be a way to construct a dialog box without that
	   separator?

The Motif 1.2 style guide shows most dialog boxes with such a separator,
and the main Motif application I use (Netscape) appears to have them (as
does the other Motif application I use, xmcd).