var win = null;
function NewWindow(mypage,myname,w,h,scroll){
LeftPosition = (screen.width) ? (screen.width-w)/2 : 0;
TopPosition = (screen.height) ? (screen.height-h)/2 : 0;
settings =
'height='+h+',width='+w+',top='+TopPosition+',left='+LeftPosition+',scrollbars='+scroll+',resizable'
win = window.open(mypage,myname,settings)
}

<!--
function popup() 
{
 var width  = 810;
 var height = 540;
 var left   = (screen.width  - width)/2;
 var top    = (screen.height - height)/2;
 var params = 'width='+width+', height='+height;
 params += ', top='+top+', left='+left;
 params += ', directories=no';
 params += ', location=no';
 params += ', menubar=no';
 params += ', resizable=no';
 params += ', scrollbars=no';
 params += ', status=no';
 params += ', toolbar=no';
 newwin=window.open("agentstour/agents_tour.html",'windowname5', params);
 if (window.focus) {newwin.focus()}
 return false;
}
// -->