Comment 2 for bug 729357

David Steele (daves) wrote :

It looks like Natty has changed how Emailers are registered. They aren't in /usr/share/gnome-control-center/default-apps/gnome-default-applications.xml anymore, and the OS is ignoring the value of the gconf variable desktop->gnome->url-handlers->mailto->command. Must be a Unity thing. I'd be willing to look into it, if someone could provide a pointer.

v1.7.2, which has been released upstream, will offer to install itself as the Preferred Email application when it is launched (from the Applications->Internet menu). But, it does that using a configuration variable that is being ignored.

This feels like "embrace and extend".