var newWin
function openwin(winurl,w,h){
  if (!w) w = 400
  if (!h) h = 200

  if (!newWin || newWin.closed) { 	
  	newWin = window.open(winurl,'','width=' + w + ',height=' + h + ',scrollbars,alwaysRaised,location=no,titlebar=no,hotkeys=no')
  } else {  
	  //window already exists, bring it forward
	  newWin.focus()
	 }
}