if (document.images) {
	enrolbuttonup = new Image();
	enrolbuttonup.src = 'images/enrol_btn.png';
	enrolbuttonover = new Image();
	enrolbuttonover.src = 'images/enrol_btn_over.png';
}

function enrolup(imagename) {
	if (document.images) {
		document[imagename].src = eval(imagename+'up.src');
	}
}

function enrolover(imagename) {
	if (document.images) {
		document[imagename].src = eval(imagename+'over.src');
	}
}