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) {
		psf_04_over = newImage("images/psf_04_over.jpg");
		psf_06_over = newImage("images/psf_06_over.jpg");
		psf_08_over = newImage("images/psf_08_over.jpg");
		psf_10_over = newImage("images/psf_10_over.jpg");
		psf_12_over = newImage("images/psf_12_over.jpg");
		psf_14_over = newImage("images/psf_14_over.jpg");
		psf_16_over = newImage("images/psf_16_over.jpg");
		psf_19_over = newImage("images/psf_19_over.jpg");
		psf_psfmap_01_over = newImage("images/psf_psfmap_01_over.gif");
		psf_missionmap2 = newImage("images/psf_missionmap2.gif");
		preloadFlag = true;
	}
}