inactive frames receive no mouse events

[MySQL Development]

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In GNU Emacs 21.4.1 (i486-pc-linux-gnu, X toolkit, Xaw3d scroll bars)
 of 2007-03-11 on raven, modified by Debian
configured using `configure  '--build=i486-linux-gnu' '--host=i486-linux-gnu' 
'--prefix=/usr' '--sharedstatedir=/var/lib' '--libexecdir=/usr/lib' 
'--localstatedir=/var/lib' '--infodir=/usr/share/info' 
'--mandir=/usr/share/man' '--with-pop=yes' '--with-x=yes' 
'--with-x-toolkit=athena' '--with-toolkit-scroll-bars' 
'build_alias=i486-linux-gnu' 'host_alias=i486-linux-gnu' 'CFLAGS=-DDEBIAN -g 
-O2''
Important settings:
  value of $LC_ALL: nil
  value of $LC_COLLATE: C
  value of $LC_CTYPE: nil
  value of $LC_MESSAGES: nil
  value of $LC_MONETARY: nil
  value of $LC_NUMERIC: nil
  value of $LC_TIME: nil
  value of $LANG: en_GB.88591
  locale-coding-system: iso-latin-1
  default-enable-multibyte-characters: t

Please describe exactly what actions triggered the bug
and the precise symptoms of the bug:

Assume: X11-windows system with "click to focus" mode.

When I have two or more frames open, and one of the frames is "active"
(has the keyboard focus), the other frames do not receive mouse events,
except left-click, which activates the frame under the mouse cursor.

If none of the emacs frames is active (e.g. an xterm window is active),
then all frames receive mouse events as expected.

Examples:

Try to paste with the middle mouse button into the active frame (works)
and into an inactive frame (nothing happens). Activate an non-emacs
window (e.g. xterm or a start a second emacs). Paste into the inactive
frames (works).

Try to scroll with the mouse wheel in the active frame (works) and in an
inactive frame (nothing happens). Activate an non-emacs window (e.g.
xterm or a start a second emacs). Happily scroll all inactive emacs
frames.

Start an ediff session. Go to a diff. Try to view the surrounding of the
diff in the two windows by scrolling with the mouse wheel. You need to
activate the frame with the diffs first. Then you need to activate the
ediff control frame again to go to the next diff.

I would like to be able to paste and scroll in all emacs frames even if
one of them is active.

Recent input:
<help-echo> M-x <down-mouse-2> <mouse-2> <return>

Recent messages:
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Loading delsel...done
Loading paren...done
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