There is a bug in the message app that reduces the number of characters available, with this bug i could easily reach 2/3/4 messages (160~ characters were not available). To fix this issue until sony comes up with a solution i suggest installing handcent (fixed it for me) Hope i helped someone. Cheers
Seems to be an issue with using accents " ~ " and " ยด " still using handcent allows many more characters
