According to a joint press release issued by Docomo, KDDI, SoftBank Mobile and eAccess (Emobile), you will now be able to SMS across carriers in Japan starting on July 13, 2011.
What does this mean for you, the humble cellphone user? No need to have the “What carrier are you?” conversation when you exchange information with a new friend. Starting on July 13, if you have a phone number, you’ll be able to call and text to all users cellphone on Japanese networks. If you’re going to make the leap from email to SMS, though, make sure you understand your data/messaging plan!
Of course, you’ll still have the option to send the fancy deco-mails that make Japanese cell phones so fun to use.
Check out the source article (English) at The Japan Times.
Ishikawa JET 
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