Wammu just got one of long wanted features - notification on incoming calls. It uses D-Bus and Desktop Notifications, so you are probably lost without some modern Linux desktop. The implementation was quite easy, if I would know that using notifications is so easy, I would have written this sooner :-).
So if you have phone connected to Wammu and somebody calls you, notification pops up and allows you to accept or reject the call. I doubt anybody needs more than this :-).
The next step will be SMS notifications, but those will be a bit more complicated.