addClass does not stick to dynamic loaded div

addClass does not stick to dynamic loaded div

thanks to IE8 not knowing how to handle last-child css I am using this global workaround, of course with an extra IE css

$(document).ready(function() { $("#footer ul li:last-child").addClass("ielast");});

however using later for a dynamic injected (.load) div it does not work

$('.some').live('click', (function() {
$("#footer nav ul").load("/menu.html #defooter");
$("#defooter li:last-child").addClass("ielast");return false

checking in firebug the div defooter does not get assigned the ielast class and I am uncertain why...
does addClass has to wait for the div to be completed loaded?

thoughts are appreciated.