function popup (URL, h, w, windowName) {
	var putItThere = null; 
	var chasm = screen.availWidth;
	var mount = screen.availHeight;
	var scr = 'no';
	var ie = /msie/i;

	var features =
		'width=' + w + 
		',height=' + h + 
		',left=' + ((chasm - w - 10) * .5) + 
		',top=' + ((mount - h - 150) * .5) + 
		',directories=no' +
		',location=no' +
		',menubar=no' +
		',scrollbars=' + scr +
		',status=no' +
		',toolbar=no' +
		',resizable=no';
	
	if (!new_window) 
	{
		var new_window = window.open (URL, windowName, features);
		if (new_window) new_window.focus();
	}
}