function newImage(arg) {
	if (document.images) {
		rslt = new Image();
		rslt.src = arg;
		return rslt;
	}
}

function changeImages() {
	if (document.images && (preloadFlag == true)) {
		for (var i=0; i<changeImages.arguments.length; i+=2) {
			document[changeImages.arguments[i]].src = changeImages.arguments[i+1];
		}
	}
}

var preloadFlag = false;
function preloadImages() {
	if (document.images) {
		id20_T_t = newImage("SIBe/20-T_t.jpg");
		id21_U_u = newImage("SIBe/21-U_u.jpg");
		id22_V_v = newImage("SIBe/22-V_v.jpg");
		id23_W_w = newImage("SIBe/23-W_w.jpg");
		id24_X_x = newImage("SIBe/24-X_x.jpg");
		id25_Y_y = newImage("SIBe/25-Y_y.jpg");
		id26_Z_z = newImage("SIBe/26-Z_z.jpg");
		id27_AA_aa = newImage("SIBe/27-AA_aa.jpg");
		id28_AB_ab = newImage("SIBe/28-AB_ab.jpg");
		preloadFlag = true;
	}
}