var isNN = (navigator.appName.indexOf("Netscape") != -1);
	
	function autoTab(input, len, e)
	{
		var keyCode = (isNN) ? e.which : e.keyCode;
		var filter = (isNN) ? [0, 8, 9] : [0, 8, 9, 16, 17, 18, 37, 38, 39, 32, 46];
		
		if(input.value.length >= len && !containsElement(filter, keyCode))
		{
			input.value = input.value.slice(0, len);
			input.form[(getIndex(input)+1) % input.form.length].focus();
		}
		
		function containsElement(arr, ele)
		{
			var found = false, index = 0;
			while(!found && index < arr.length)
			{
				if(arr[index] == ele)
				{
					found = true;
				}
				else
				{
					index++;
				}
			}
			return found;
		}
		
		function getIndex(input)
		{
			var index = -1, i = 0, found = false;
			while(i < input.form.length && index == -1)
			{
				if (input.form[i] == input)
				{
					index = i;
				}
				else
				{
					i++;
				}
			}
			return index;
		}
		return true;
	}