if (document.all && document.styleSheets && document.styleSheets[0] && document.styleSheets[0].addRule){
	var ms = navigator.appVersion.indexOf("MSIE")
	var msVer = parseInt(navigator.appVersion.substring(ms+5, ms+6));
	
	if (msVer <= 6){
		document.styleSheets[0].addRule('ul#menu li', 'background:url(\"../img/tab_leftcorner.gif\") no-repeat left top;margin:0 4px 0 0;');
		document.styleSheets[0].addRule('ul#menu li a', 'background:url(\"../img/tab_rightcorner.gif\") no-repeat right top;');
	}
}