// this function is needed to work around 
  // a bug in IE related to element attributes
  function hasClass(obj) {
     var result = false;
     if (obj.getAttributeNode("class") != null) {
         result = obj.getAttributeNode("class").value;
     }
     return result;
  }   

function stripe(_id) {
    // the flag we'll use to keep track of 
    // whether the current row is odd or even
    var even = false;
    // if arguments are provided to specify the colours
    // of the even & odd rows, then use the them;
    // otherwise use the following defaults:
    var evenColor = arguments[1] ? arguments[1] : "even";
    var oddColor = arguments[2] ? arguments[2] : "odd";
    // obtain a reference to the desired table
    // if no such table exists, abort
    var ul = document.getElementById(_id);
    var lis = ul.getElementsByTagName("li");
    // and iterate through them...
    for (var h = 0; h < lis.length; h++) {
		var myli = lis[h];
		// avoid cells that have a class attribute
		// or backgroundColor style
        if (!hasClass(myli)) {
        	myli.className = even ? evenColor : oddColor;
        }
        // flip from odd to even, or vice-versa
        even =  ! even;
	}
}