So it looks like the Enter key behavior is controlled by the Gtk "activates_default" property. In applet.glade, it's set to "TRUE" for the wpa_psk_entry, and "FALSE" for wep_key_entry.
So it looks like the Enter key behavior is controlled by the Gtk "activates_default" property. In applet.glade, it's set to "TRUE" for the wpa_psk_entry, and "FALSE" for wep_key_entry.