In firefox and Chrome its working perfect
but when im using Explorer 9/8
the following script isn't always working (only if i refresh the page a few times)

i've added the $.ajaxSetup({ cache: false}); statement since it wasn't working even in explorer 9 without that statement..
how can i fix this annoying error? i am using jQuery 1.2.6 (and i can't update).
HTML Code:
	<script type="text/javascript">
		$.ajaxSetup({ cache: false});
		function ajax_load(_tag)
			$.get("<?php echo $this->ajax_url; ?>", { <?php echo $this->ajax_get_string; ?>, tag: _tag.slice(1) },
		temp_tag = window.location.hash;
		var _tag="#content";
		if (window.location.hash.length > 0) {
			_tag = window.location.hash;
		$('.tab-menu li a').click(function() {
			_tag = $(this).attr('href');