First of all, keep out unless you are a Japanese.
To be honest, I was at a loss whether I should rate this module or not; in fact, the module is obviously confined to the Japanese users, and for this reason, its documentation, too, is written in Japanese. My work, however, owes much to the module, and I decided to rate it.
As with Mail::Address::MobileJp by Miyagawa-san, the module validates mobile mail addresses distributed from the Japanese mobile phone carriers; the former should be updated as its author says, whereas the latter has been maintained after a fashion, I reckon. At first blush, validating the addresses would appear easy, but that is by no means the case as a matter of fact, for historical reasons as to the Japanese mobile phone carriers.
In any case, I'd like to recommend the module to the Japanese users.