This bug was fixed in the package gtk+3.0 - 3.2.0-0ubuntu3
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gtk+3.0 (3.2.0-0ubuntu3) oneiric-proposed; urgency=low
* debian/patches/043_ubuntu_menu_proxy.patch: Fix menu accelerator
support for UI generated with GtkBuilder or using GtkMenus
submenus. Instead of using the
** Package changed: unity (Ubuntu) = gtk+3.0 (Ubuntu)
** Changed in: gtk+3.0 (Ubuntu)
Status: Invalid = Fix Committed
** Changed in: gtk+3.0 (Ubuntu)
Assignee: Canonical Desktop Experience Team (canonical-dx-team) = Marco
Trevisan (Treviño) (3v1n0)
** Changed in: gtk+3.0 (Ubuntu
** Changed in: ubuntu
Status: Fix Committed = Fix Released
** Changed in: Ubuntu Oneiric
Status: Fix Committed = Fix Released
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Ok, I've made some more testing and I've also found a solution, but
before checking if that's right let's discuss a little.
Basically the issue we're always reproducing when using a gtkbuilder-based app,
can also happening when manually programming our interface and basically when
we're doing
