] The Federal Communications Committee and the Justice
] Department are at loggerheads over a new problem in the
] war on terror: how to listen in on Internet phone calls.
] Thanks to the blistering growth of VoIP (Voice over
] Internet Protocol) services, which have been adopted by
] approximately 10 million people worldwide so far, law
] enforcement officials now worry that wiretapping may one
] day become technically obsolete. If traditional phone
] lines go the way of the horse and carriage, will the FBI
] still be able to listen in on Internet phone calls? How
] would it go about tapping one? Is it even possible?

The gateways between the Internet VoIP based phone networks and the traditional phone networks are about the only places I can picture CALEA-compliant (like) hardware/software existing. Purely Internet based VoIP networks are going to resist any type of monitoring, use crypto, and exist even if they are outlawed.

Can They Hear You Now? - How the FBI eavesdrops on Internet phone calls (and why it sometimes can't). By David S. Bennahum