[krnfrk6663]

It depends on the phone and the carrier. When those extra characters are added, it adds different hidden codes then what you see, or it tries to convert it to another format.. I am not really sure. I just know it adds some coding to it, that isn't normal for the language we speak, foreign languages have a different coding format, thus adding characters that are hidden from our view. (It's the way sms works here.) There is more to it, but I'm not that knowledgeable on this subject. Anything else, I'd say hit a wiki on sms. You're bound to find something there.