Does a 2002 Toyota Highlander require a chip key to start?

I have a 2002 Highlander that I bought new. I recall that the sales person said the key was specially equipped with a computer chip. My wife recently got a key made. The top is not as round or fat as our original keys - I'm not sure there is a chip inside. According to my doentation and what the dealer shows on the computer, the vehicle does have the engine immoblizer. But when I insert the key into the ignition, the car starts. Is this key a 'chip key'? Or do I have a broken immobilizer? I had my regular key in my pocket, but I was told that it had to be in close proximity to the iginition? Anyone have any ideas?