Could you define "doesn't work"? Do you mean the file doesn't have the UTF-8 BOM at the beginning?
James R. Perkins
Thanks for your reply.
"doesn't work" means that the supplementary characters were expected to be displayed though,
"?" were displayed instead of the supplementary characters.
After I deleted the old log file manually, the supplementary characters were written out well in my log file.
I think that the original log file was made as SJIS encoding firstly,
so after that althought I had changed my log4.xml,
setting log file to UTF-8 encoding value,for the log file had been SJIS,
the supplementary characters couldn't been written out well.
Sorry for the late reply, and thank you very much!