function register_formfield_change(that) {
	var f = document.forms['frm_register'];

	if(that.name.substr(0, 8) == 'billing_') {
		register_copy_billing(f.register_copy_billing_info);
	}
	else if(that.name.substr(0, 9) == 'shipping_') {
		f.register_copy_billing_info.checked = 0;
	}
	else return;
}

function register_copy_billing(that) {
	if(!that.checked) return;
	var f = document.forms['frm_register'];

	var copyfields = new Array(
		'firstname',
		'lastname',
		'company',
		'address_1',
		'address_2',
		'city',
		'state',
		'zip',
		'country'
	);

	for(var i=0; i<copyfields.length; ++i) {
		f.elements['shipping_'+copyfields[i]].value = f.elements['billing_'+copyfields[i]].value;
	}
}