I'm using python GTK under Gnome (Gnome 3 in Fedora 15).
I'd like to catch events when the user double clic on the icon in the tray area.
I found that "activate" signals is called when the user do a single clic, but can't find the signal or a proper way to call a method when the user double clic on it.
How can I do ?
Thanks for your help!
You can't. Gtk+ itself doesn't even know if it was single or double clicked.
From the Gtk+ documentation about the ::activate signal:

Gets emitted when the user activates the status icon. If and how status icons can activated is platform-dependent.

Interestingly Qt knows about this (it has Trigger and DoubleClick). Maybe you can work around this by using ::button-press-event instead and counting it, but I'm not sure this can be called the recommended way.
Also, a personal note as a user: I prefer status icons that are activated by a single click.
gtk.StatusIcon with double click