var plus
var minus

function jPreloadImages(){

	plus = new Image();
	plus.src = "images/plus.gif";

	minus = new Image();
	minus.src = "images/minus.gif";
}

function jToggleDisplay(oButton, oDiv)   {

	if ((oDiv.style.display == "") || (oDiv.style.display == "none"))	{
		oDiv.style.display = "block";	//show the div
		oButton.src = minus.src;		
	}	else {
		oDiv.style.display = "none";	//hide the div
		oButton.src = plus.src;		
	}
}