function addLoadEvent(func) {
  var oldonload = window.onload;
  if (typeof window.onload != 'function') {
    window.onload = func;
  } else {
    window.onload = function() {
      oldonload();
      func();
    }
  }
}

function menuhover() {
	if(document.getElementById("languagemenu")) {
		var LIs = document.getElementById("languagemenu").getElementsByTagName("LI");
		for (var i=0; i<LIs.length; i++) {
			LIs[i].onmouseover=function() {
				for(var j=1; j<= i; j++) {
					var welkompic = "wp"+j;
					document.getElementById(welkompic).style.visibility = "hidden";
				}
				var LInumber = this.id.replace("w","");
				var welkompic = "wp"+LInumber;
				document.getElementById(welkompic).style.visibility = "visible";
			}
		}
	}
}

addLoadEvent(menuhover);