function pop(url,title,winwidth,winheight) {
	popped=window.open(url,title,'width='+winwidth+',height='+winheight+',status=yes,resizeable=yes,menubar=yes');
	if (screen.width) {
		xpos=(screen.width)/2-(winwidth/2);
		ypos=(screen.height)/2-(winheight/2);
		popped.moveTo(xpos,ypos);
	}
}