[noonespecial]

It is not the 2.4Ghz radiation that causes the trouble with pacemakers. Its the plain old magnetic field generated by the inductive inrush from the giant coils that convert the power to feed to the magnetron tube in the microwave. Any large inductive load poses the same risk.

[dredmorbius]

I'm getting slightly different information. The best "how do Microwaves interfere with pacemakers" info I could find was from The Straight Dope, which indicated that it was actually microwave leakage, not the coils themselves, which induced the current. And I'm aware that among the reasons you don't nuke metallic objects is because of the charges induced. Another source showing effects of various EMR frequencies indicated that induced currents were among the effects of microwave and other longer-wave radiation.

That said, other risks for pacemakers include store anti-theft devices, most of which are also inductive coils so far as I understand.

[dredmorbius]

http://www.epa.gov/rpdweb00/understand/ionize_nonionize.html

Effects of radiation chart showing induced current effect.