Comment 2 for bug 1017772

Just for the record (or, how I've solve the problem),
I've found a very nice solution to use GIMP in the "multiple window"
mode inside the UNITY (ubuntu 12.04) enviroment. Is just run the GIMP
with the command:

in terminal:

UBUNTU_MENUPROXY= gimp
(That will place the menus in the windows instead of the top bar)

OR
APPMENU_DISPLAY_BOTH=1 gimp
(that will place the menus both in the top bar and in the windows)

via ALT+F2:

env UBUNTU_MENUPROXY= gimp

env APPMENU_DISPLAY_BOTH=1 gimp

Or make a "gimp.desktop" file with an text editor and place in the launcher:

[Desktop Entry]
Version=2.6.12
Type=Application
Terminal=false
Exec= env APPMENU_DISPLAY_BOTH=1 gimp
Name=Gimp
GenericName=Gimp Painter
Icon=/usr/share/icons/hicolor/scalable/apps/gimp.svg

thanks,
Udan