window-size-fixed behaviour on emacs22-gtk

[hjuvi]

Hello,

Changing from emacs21 to emacs22-gtk (on Ubuntu desktop), I'm no
longer able to have window-size-fixed work properly - or at least how
I expect it to work :)

I've been using it to have a window with fixed size in the middle of
the frame.

On emacs21, I can change the size of other windows, this particular
one moves up and down but always keep the same height. This is how I
expect it to work...

On emacs22-gtk, if I drag from the upper side (mode-line) of the
window, it enlarges (which should not happen). If I drag from the
lower side of the window, it doesn't move at all !...

Why is the behaviour different between emacs21 and emacs22-gtk ?
The behaviour on emacs21 matches with my needs (and with the idea of
window-size-fixed, I believe), whereas I cannot get it work properly
on emacs22-gtk.

Below is some lisp code to show the problem : you can put it in a file
test.el, and call : emacs -q -l test.el

(setq inhibit-startup-message t)
(split-window-vertically)
(split-window-vertically)
(split-window-horizontally)
(switch-to-buffer (get-buffer-create "buffer1"))
(select-window (next-window))
(switch-to-buffer (get-buffer-create "buffer2"))
(select-window (next-window))
(switch-to-buffer (get-buffer-create "buffer3"))
(select-window (next-window))
(switch-to-buffer (get-buffer-create "buffer4"))
(select-window (previous-window))
(enlarge-window (- 5 (window-height)))
(setq window-size-fixed t)

"buffer3" window is supposed to have fixed size.

Thanks to anyone who can help me...

If the behaviour of window-size-fixed is unpredictable - depending on
which version of emacs I use - I will have to remove the feature that
need it, so I hope there is a solution...