How can one achieve the same thing using Cookies to pass along the "aff_sub"?

change_href.js

<script>
$(document).ready(function () {
	$(window).load(function () {
		if (getURLParameter("aff_sub") != "null") {
			var href = $("a[href*='#aff_sub#']").attr("href");
			href = href.replace(/#aff_sub#/g,getURLParameter("aff_sub"));
			$("a[href*='#aff_sub#']").attr("href",href);
		}
	});
});
</script>