Multiple frames don't work with buffer tabs off

I've discovered an interesting problem in the current 21.5 Windows version. 
If you have buffer tabs turned off and open another frame, that new frame 
will never paint its client area and can't be given keyboard focus for 
typing.  To reproduce this run XEmacs -vanilla, select 
Options->Display->Buffer Tabs Visible to turn off buffer tabs, then create 
a new frame (for example C-x 5 2).  The new frame works in the sense that 
menus and tool bar buttons work, but the client area is never painted.

I've tracked this down as far as I can easily.  It is calling 
mswindows_handle_paint for the frame in response to a WM_PAINT message. 
However the call to BeginPaint there returns an empty paint rectangle so 
somehow Windows thinks nothing needs to be painted.  I'm not sure when this 
started happening since I haven't built a current CVS version of XEmacs for 
a while.  I'm running on Win2K SP2 if that matters.

Mike Alexander                <mailto:[email protected]>
Arbortext, Inc.               +1-734-997-0200