How to make bulb talk to controller?

I need to somehow make a light bulb(operating at 220V AC) communicate back to Make controller by a xbee/zigbee chip. Aim is to have two xbee chips, one on the bulb and one on Make controller so that I can programitically turn on and off the bulb wirelessly. I am not sure about what circuit to use to build the bulb + relay + xbee part Any help to start pls?

my initial thought on the subject is that whatever is connected to the relay/triac/etc. will have to know it's own state because it has to maintain an active line. Even if you used a solenoid driven switch (which could loose it's state), you can force it on or off without knowing which state it is currently in. So, if the xbee (which I know nothing about) can tell you the state of a single digital variable, and receive a command to switch the state, then I think you are golden... EBo --