different fonts in different frames are named the same

[Sam Steingold]

GNU Emacs 21.3.50.1 (i386-msvc-nt5.0.2195)
 of 2003-06-16 on WINSTEINGOLDLAP
--with-msvc (12.00)

I have two frames side by side and they have visibly different fonts
(e.g., one displays bold face and the other does not!), even though
        (frame-parameter (selected-frame) 'font)
returns the same string on both of them.
        (frame-parameter (selected-frame) 'height)
also returns the same number also even though one frame contains
visibly different number of lines (although the frame height in
centimeters would be the same).

When I try S-mouse-1 (mouse-set-font), the actual font does not change,
even though the frame size does.

I am confused - have anyone seen anything like that?
what could be the cause?

-- 
Sam Steingold (http://www.podval.org/~sds) running RedHat9 GNU/Linux
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