var winReference = null;
function openPositionedWindow(url, name, width, height, x, y, status, scrollbars, statusbar, toolbar, menubar,  openerName) {
	
	// ie 4.5 and 5.0 mac - windows are 2 pixels too short; if a statusbar is used, the window will be an additional 15 pixels short
	var agent = navigator.userAgent.toLowerCase();
	if (agent.indexOf("mac") != -1 && agent.indexOf("msie") != -1 && (agent.indexOf("msie 4") != -1 || agent.indexOf("msie 5.0") != -1) ) {
		height += (status) ? 17 : 2;
	}

	// Adjust width if scrollbars are used (pc places scrollbars inside the content area; mac outside) 
	width += (scrollbars != '' && scrollbars != null && agent.indexOf("mac") == -1) ? 16 : 0;

	var properties = 'width=' + width + ',height=' + height + ',screenX=' + x + ',screenY=' + y + ',left=' + x + ',top=' + y + ((status) ? ',status' : '') + ',scrollbars' + ((scrollbars) ? '' : '=no') + ((statusbar) ? ',' + statusbar : '');
	var reference = openWindow(url, name, properties, openerName);


	return reference;
}
function openCenteredOnOpenerWindow(url, name, width, height, status, scrollbars, statusbar, toolbar, menubar, personalbar, openerName) {
	var centerX = 0;
   var centerY = 0;
   if (window.screenX != null && window.outerWidth) {
      centerX = window.screenX + (window.outerWidth / 2);
      centerY = window.screenY + (window.outerHeight / 2);
   }
   else if (window.screenLeft) {
      if (document.documentElement) {
         centerX = window.screenLeft + (document.documentElement.offsetWidth / 2);
         centerY = window.screenTop + (document.documentElement.offsetHeight / 2);
      }
      else if (document.body && document.body.offsetWidth) {
         centerX = window.screenLeft + (document.body.offsetWidth / 2);
         centerY = window.screenTop + (document.body.offsetHeight / 2);
      }
   }
   
   if (centerX == 0) {
      openCenteredWindow(url, name, width, height, status, scrollbars, statusbar, toolbar, menubar,  openerName);
   }
   var x = parseInt(centerX - (width / 2));
   var y = parseInt(centerY - (height / 2));
	if (!status) status = '';
	if (!openerName) openerName = '';
	var reference = openPositionedWindow(url, name, width, height, x, y, status, scrollbars, statusbar, toolbar, menubar,  openerName);
	return reference;
}	
function openWindow(url, name, properties, openerName) {

	// ie4.x pc can't give focus to windows containing documents from a different domain
	// in this case, initially load a local interstisial page to allow focussing before loading final url
	var agent = navigator.userAgent.toLowerCase();
	if (agent.indexOf("msie") != -1 && parseInt(navigator.appVersion) == 4 && agent.indexOf("msie 5") == -1 && agent.indexOf("msie5") == -1 && agent.indexOf("win") != -1 && url.indexOf('http://') == 0) {
		winReference = window.open('about:blank', name, properties);
		
		setTimeout('if (winReference && !winReference.closed) winReference.location.replace("' + url + '")', 300);
	}
	else {
		winReference = window.open(url, name, properties);
	}

	// ie doesn't like giving focus immediately (to new window in 4.5 on mac; to existing ones in 5 on pc)
	setTimeout('if (winReference && !winReference.closed) winReference.focus()', 200);
	
	if (openerName) self.name = openerName;
	return winReference;
}