function mainmenu(){


$(" #nav ul ").css({display: "none"}); // Opera Fix
$(" #nav li").hover(function(){
		$(this).find('ul:first').css({visibility: "visible",display: "none"}).slideDown(250);
		},function(){
		//alert('ok');
			
			$(this).find('ul:first').css({visibility: "hidden"});
		});
}

 $(document).ready(function(){	
 if(navigator.userAgent.indexOf("Firefox")!=-1){ 
//$("#nav ul.ul_biller_lier").css({marginLeft: "-199px"});
}
if(navigator.userAgent.indexOf("MSIE 6") != -1) {
	//$("#nav ul.ul_biller_lier").css({marginLeft: "-199px"});
}
	mainmenu();
});