var isIE=false, isNN=false, isGeko=false;

function getClientInfo(){
	if(document.all){
	isIE=true;
	}
	if (document.layers){
	isNN=true;
	}
	if(document.getElementById){
	isGeko=true;
	}
}

function setObj(lay) {
	// check if layer exist
	if(isNN) {
	tmpObj=eval("document."+lay);
	}
	if(isIE) {
	tmpObj=eval("document.all."+lay);
	}
	if(isGeko) {
	tmpObj=eval("document.getElementById('"+lay+"')");
	}
	
	//append style attrib & return if layer exist
	if(tmpObj){
	if(isNN) {
	theObj=tmpObj;
	}
	if(isIE){
	theObj=eval("document.all."+lay+".style");
	}
	if(isGeko){
	theObj=eval("document.getElementById('"+lay+"').style");
	}
 	return(theObj);
 	} else {
  	alert("element ["+lay+"] does not exist");
 	}
}


//layer an eine Position (x,y) bewegen
function setLayerPos(lay,x,y) {

	setObj(lay);
	theObj.left=x;
	theObj.top=y;
}

//layer einblenden
function show(lay) {
	setObj(lay);
	theObj.visibility="visible";
	}
	
//layer ausblenden
function hide(lay) {
	setObj(lay);
	theObj.visibility="hidden";
	}