var img_on = new Image();  
img_on.src = global_root_path + "webImages/tnviOvr.gif"; 
var img_off = new Image();  
img_off.src = global_root_path + "webImages/tnviNor.gif"; 

function changeImage(objId, typVal){
	var imgName1 = document.getElementById('menu'+ objId);
	var secImg = objId + 1; 
	var imgName2 = document.getElementById('menu'+ secImg);
	if(typVal == 1){
		imgName1.src = img_on.src;
		imgName2.src = img_on.src;
	}else{
		imgName1.src = img_off.src;
		imgName2.src = img_off.src;
	}
}