You cannot have an encoding other than the one supported by the MIDP implementation. All MIDP requires an implementor to do is to support Basic-Latin-1 and Latin-1-Supplement encodings. Support for any other encoding is upto the implementor due to space constraints in CLDC. So you have to actually check with your phone provider (Sony, Nokia) to see if that model supports your encoding. It might, since they want to cover the local market. Easy way to find it is do something that uses your encoding and see if it throws UnsupportedEncodingException or not. If it does, bad luck!