If you are using the native iconv implementation on Solaris
instead of libiconv, you'll need to make sure that you have
the converters between locale encodings and UTF-8 installed.
At a minimum you'll need the SUNWuiu8 package. You probably
should also install the SUNWciu8, SUNWhiu8, SUNWjiu8, and
SUNWkiu8 packages.
Regards,
Owen