if (!Array.prototype.indexOf)
{
	Array.prototype.indexOf = function(searchElement /*, fromIndex */)
	{
	"use strict";

	if (this === void 0 || this === null)
		throw new TypeError();
 
	var t = Object(this);
	var len = t.length >>> 0;
	if (len === 0)
	  return -1;

	var n = 0;
	if (arguments.length > 0)
	{
	  n = Number(arguments[1]);
	  if (n !== n) // shortcut for verifying if it's NaN
		n = 0;
	  else if (n !== 0 && n !== (1 / 0) && n !== -(1 / 0))
		n = (n > 0 || -1) * Math.floor(Math.abs(n));
	}
 
	if (n >= len)
	  return -1;
 
	var k = n >= 0
		  ? n
		  : Math.max(len - Math.abs(n), 0);
 
	for (; k < len; k++)
	{
	  if (k in t && t[k] === searchElement)
		return k;
	}
	return -1;
  };
}