why is it ?You are told to turn cell pones off?

the frequency cellphones used to operate on interfered with the older versions of the airplanes equipment but really dont affect the newer equipment

better safe then sorry thoug

as for the rest of your question, i have no idea... it seems kinda retarded that they would allow matches but not lighters. but i guess terrorists could potential use the fluid in lighters to create a bomb where as matches just burn

The data support[s] a conclusion that continued use of portable RF-emitting [radio frequency-emitting] devices such as cell phones will, in all likelihood, someday cause an accident by interfering with critical cockpit instruments such as GPS receivers. Because pilots increasingly rely on GPS technology to aid in landings, such interference could be potentially catastrophic.

For the lighters, read here http://www.smokersclubinc.com/modules.php?name=New...

There is a theory that the radiation from cell phones can affect the radio navigation instruments of the airplane. Personally, I consider this bogus (I'm an electronic engineer, licensed pilot, and aircraft owner), but one must keep the flight crew happy so turn your phone off.

Because the tobacco industry lobbied lawmakers to keep lighters and matches allowable on airlines.

You're not allowed matches...

because it could interfere with all the...navigation..crap.