module Mail::Utilities

def quote_phrase( str )

in double quotes, otherwise returns the string unmodified
If the string supplied has PHRASE unsafe characters in it, will return the string quoted

def quote_phrase( str )
  if str.respond_to?(:force_encoding)
    original_encoding = str.encoding
    ascii_str = str.to_s.dup.force_encoding('ASCII-8BIT')
    if Constants::PHRASE_UNSAFE === ascii_str
      dquote(ascii_str).force_encoding(original_encoding)
    else
      str
    end
  else
    Constants::PHRASE_UNSAFE === str ? dquote(str) : str
  end
end