function openPopUp(popURL, popName, popWidth, popHeight, popParams){	
	if( !window.outerWidth ) // for IE
		if( window.screenLeft ){ // under windows
			destX = (window.screenLeft-8) + (document.body.offsetWidth+8)/2 - popWidth/2;
			destY = (window.screenTop-142) + (document.body.offsetHeight+142)/2 - popHeight/2;
		}else{ // under MacOS
			destX = window.screen.width/2 - popWidth/2;
			destY = window.screen.availHeight/2 - popHeight/2;
		}
	else{ // for NS
			destX = window.screenX + window.outerWidth/2 - popWidth/2;
			destY = window.screenY + window.outerHeight/2 - popHeight/2;
	}
	destX=Math.round(destX);
	destY=Math.round(destY);
	winObj=window.open(popURL, popName, 'left='+destX+',top='+destY+',width='+popWidth+',height='+popHeight+','+popParams);
	winObj.focus();
	return winObj;
}