var popup_array = Array();
function popup(url, popup_name, options) {
	var cur_popup = popup_array[popup_name];
	var is_popup_defined = (typeof(cur_popup) == 'object');
	var is_popup_open = (is_popup_defined)
		? !(cur_popup.closed)
		: false;

	if ( is_popup_defined && is_popup_open ) {
		cur_popup.document.write (' ');
		cur_popup.focus();
		cur_popup.location.href = url;
		cur_popup.focus();
	} else if ((is_popup_defined && !is_popup_open) || !is_popup_defined) {
		popup_array[popup_name] = window.open(url, popup_name, options);
	}
}