[da_ff]

пришлось писать свое

function convertSpecSymbols (str, toText) {
  var
    symbols = [
      ['&',     '&'],
      ['&lt;',      '<'],
      ['&gt;',      '>'],
      ['&and;',     '^'],
      ['&sim;',     '~']
    ],
    pos = -1;

  if (typeof toText == 'undefined' || toText) {
    for (var i = 0, n = symbols.length; i < n; i++) {
      while ((pos = str.indexOf(symbols[i][0], pos + 1)) != -1) {
        str = str.substring(0, pos) + symbols[i][1] + str.substring(pos + symbols[i][0].length);
      }
    }
  } else {
    for (var i = 0, n = symbols.length; i < n; i++) {
      while ((pos = str.indexOf(symbols[i][1], pos + 1)) != -1) {
        str = str.substring(0, pos) + symbols[i][0] + str.substring(pos + symbols[i][1].length);
      }
    }
  }
  return str;
}