Comment 5 for bug 346477

That's fair enough, since normally you expect menus to close when you click outside of them, even if it is a right click.

Actually I found that the behavior was erratic, sometimes I do get a normal menu, other times it acts like you right clicked on the panel where the menus are.

This bug has been filed upstream -
http://bugzilla.gnome.org/show_bug.cgi?id=576242