Unlocking a CAR with Mobile phone

You can unlock your car by a mobile phone & a set of spare keys lying at home.
For Example:

1. A man got out of his car & realizes that he forgot his car keys in the car. Then he calls his wife.
2. His wife lifts the phone & he tells her to hold the set of spare keys of the car near her mobile phone & then to press UNLOCK, he puts the mobile near the car.
3. So, the waves get passed and the Car gets UNLOCKED.

Did you try this ever?? Try it on your own risk*