1. Field of the Invention
The present invention relates to a mobile communication device such as a mobile phone in which a contactless IC card is built, a mobile communication device control program, and a mobile communication device control method. In particular, the present invention relates to a mobile communication device having a function to release a lock on a password when a password for authorizing use is locked in case of using a contactless IC card, a mobile communication device control program, and a mobile communication device control method.
2. Description of the Related Art
There has been a conventional contactless IC card (hereinafter simply called an IC card in several cases) or a mobile phone in which a contactless IC card is built. There also have been cases that, for example, an expensive item is paid with a credit card using the IC card on shopping and that a personal computer (hereinafter called a PC) is logged in for business purpose. In these cases, if a password (PIN: Personal Identification Number) is entered incorrectly a particular number of times (for example, three times), the PIN is locked and use of the IC card is prohibited. That is, if a PIN authentication error is repeated, the IC card function is protected to maintain security.
Alternatively, if a PIN authentication error is unintentionally repeated by mistake by the user of a mobile phone and if the PIN is locked to protect the IC card function, the user of the mobile phone asks a system manager to release the lock, i.e., to release the protection.
There is disclosed a technique for releasing lock of a PIN by use of a mobile phone though disclosed is neither a contactless IC card nor a mobile phone having a built-in contactless IC card. This technique is now described as a reference. For example, in advance, a lock release code is set in a mobile phone from a subscriber identification module. In case of releasing lock, a random number is transmitted from the mobile phone to the subscriber identification module. As a result, the subscriber identification module calculates a lock release calculation value by use of the received random number and a lock release code and transmits the lock release calculation value to the mobile phone. On the other side, the mobile phone performs unlocking only when the received lock release calculation value agrees with a lock release calculation value which the mobile phone internally calculates (see, for example, Jpn. Pat. Appln. Laid-Open Publication No. 11-275215, paragraphs 0019 to 0037, and FIG. 1).
However, if lock release (release of protection) is carried out when the PIN of a contactless IC card built in a mobile phone is locked, the system manager releases the lock of the PIN after identifying the client of the lock release by a meeting or telephone call to identify whether the client is the actual user of the mobile phone or a malicious third party who is “masquerading”. However, this method of confirmation requires a lot of labor and time of the system manager to release the lock of the PIN.
The technique according to the above publication No. 11-275215 requires human manipulation by an operator and so requires also a lot of labor and time of a system manager.