A new mobile phone in Japan takes security pretty seriously: It can recognize its owner, automatically locks when the person gets too far away from it and can be found via satellite navigation if it goes missing.

The P903i from NTT DoCoMo, Japan's top mobile carrier, comes with a small black card about the size of a movie-ticket stub. The card works as a security key by connecting wirelessly with the cell phone.

If an owner keeps the card in a bag or pocket, the phone recognizes when the card moves too far away and locks automatically to prevent someone from making a call. The user can choose to have the phone lock when it is 26 feet, 66 feet or 130 feet away.

People who lose their security cards can punch in a password to unlock the phone. But they will have to buy a new card to set the lock again.

The extra security is handy because, like other recent Japanese phones, the P903i can be used as a credit card or a prepaid cash card.

Of course, the new security feature won't prevent snoops from getting information from the phone — reading personal e-mails, say — if it is within the set distance of the security key.

To guard against such intruders, users can activate the phone's facial identification feature.

Here's how that works. Owners must first take at least three photos of themselves with the phone's camera. Up to 10 can be shot, in various situations — with and without glasses, with and without makeup, indoors and outdoors.

Then, if the facial-recognition feature is turned on, before accessing the handset a user has to take a picture of himself with the camera. The phone analyzes features such as distance between the eyes and unlocks if the image matches the stored data.

A separate function recognizes whether the eyes are blinking — in case someone tries to show the owner's photo to gain fraudulent entry. Not only that, a four-letter password can be added to this process, to guard against an identical twin getting unauthorized access.

"Security is increasingly a key function for mobile phones as they become loaded with more sophisticated features," said NTT DoCoMo spokeswoman Mamiko Tanaka. "Handset makers are all competing to come up with interesting ways to strengthen security."

Should the P903i get lost, the user can track it with its onboard Global Positioning System. After entering the phone number into a Web site, the owner will see a map showing the phone's rough location — directions via GPS can be off by several hundred feet.

Pricing for the phone, which is manufactured by Matsushita Electric Industrial Co. and planned for sale in the next few months, has not yet been announced. Using the GPS service to look for a missing phone will cost $2.50 a pop.