>UnsupportedEncodingException</a></pre>
<div class="block">Encode a RFC 822 "word" token into mail-safe form as per
 RFC 2047. <p>

 The given Unicode string is examined for non US-ASCII
 characters. If the string contains only US-ASCII characters,
 it is returned as-is.  If the string contains non US-ASCII
 characters, it is first character-encoded using the platform's
 default charset, then transfer-encoded using either the B or 
 Q encoding. The resulting bytes are then returned as a Unicode 
 string con