var winhandle = null;

function popUp(aURL, aImageWidth, aImageHeight) {

  var lWindowWidth  = Math.min(aImageWidth,  screen.availWidth);
  var lWindowHeight = Math.min(aImageHeight, screen.availHeight);

  if ((winhandle != null) && (! winhandle.closed)) {
      
  winhandle.location.replace(aURL);
	  
  }
  else
  {
  var lOptions = 'width=' + aImageWidth + ',height=' + aImageHeight + ',resizable,scrollbars';
  winhandle = window.open(aURL, "imagewin", lOptions);
  }
			  
  winhandle.focus();
			    
  }
			    
  function PageLoaded() {
  imagepreload = new Image;
  imagepreload.src = "www.upinkasu.cz-akce_1.jpg";
  }
window.onload=PageLoaded;