Yikes - FBI can listen to your cell phone even when turned OFF

from ABC post it indicates that ...The FBI can listen to everything you say, even when the cell phone is turned off...

Yikes - u're not safe now. Well if u've got interesting stuff going on that the FBI are taking some notice of u then u'd better b careful.
Be interested in seeing HOW this really works if someone has more low level details.

Found via O'Reilly blog