Unity global menu causes handlers of the "activate" signal of Gtk.Action to be emptied

If you launch banshee 2.6.2 or banshee 2.9.0 in Ubuntu 14.04 and start playing a song, and then go to the "Edit" menu, you will not see an option to set up the rating of the song.

The culprit of this is Unity's Global Menu, because the RatingSet menu appears fine when launching banshee with UBUNTU_MENUPROXY=0.

Under the hood, the reason of why this menu is not attached when running inside unity is because adding a handler to the signal "activate" of a Gtk.Action has no effect (maybe Unity is removing all the handlers of this signal?).

ProblemType: Bug
DistroRelease: Ubuntu 14.04
Package: unity 7.1.2+14.04.20140220-0ubuntu1
ProcVersionSignature: Ubuntu 3.13.0-12.32-generic 3.13.4
Uname: Linux 3.13.0-12-generic x86_64
ApportVersion: 2.13.2-0ubuntu5
Architecture: amd64
CompizPlugins: No value set for `/apps/compiz-1/general/screen0/options/active_plugins'
CurrentDesktop: Unity
Date: Sat Mar 1 21:23:34 2014
InstallationDate: Installed on 2014-02-25 (4 days ago)
InstallationMedia: Ubuntu 14.04 LTS "Trusty Tahr" - Alpha amd64 (20140224)
SourcePackage: unity
UpgradeStatus: No upgrade log present (probably fresh install)