var win= null;
function popup(mypage,myname,w,h){
	var winl = (screen.width-w)/2;
	var wint = (screen.height-h)/2;
	var settings ='height='+h+','
		+'width='+w+','
		+'top='+wint+','
		+'left='+winl+','
		+'scrollbars=yes,'
		+'resizable=yes';
	win=window.open(mypage,myname,settings);
	if(parseInt(navigator.appVersion) >= 4) {
		win.window.focus();
	}
}
//popup dimensions on startup 728x400
var width=728;
var height=400;
function popup(mypage,myname){
	var winl = (screen.width-width)/2;
	var wint = (screen.height-height)/2;
	var settings ='height='+height+','
		+'width='+width+','
		+'top='+wint+','
		+'left='+winl+','
		+'scrollbars=yes,'
		+'resizable=yes';
	win=window.open(mypage,myname,settings);
	if(parseInt(navigator.appVersion) >= 4) {
		win.window.focus();
	}
}