 encoding will
 be used when necessary.  The default is false. <p>

 In addition, the <code>mail.mime.charset</code> System property can
 be used to specify the default MIME charset to use for encoded words
 and text parts that don't otherwise specify a charset.  Normally, the
 default MIME charset is derived from the default Java charset, as
 specified in the <code>file.encoding</code> System property.  Most
 applications will have no need to explicitly set the default MIME
 charset.  In cases where the de