/* 
The code in this script checks to see if the browser is 
either Navigator 4.0 (or later) or IE 4.0 (or later).

If not, then the page won't run.

*/

var RunningIE4
RunningIE4 = (msieversion() >=4);

function msieversion() {
var ua = window.navigator.userAgent
var msie = ua.indexOf ( "MSIE " )
if ( msie > 0 ) // is Microsoft Internet Explorer; return version number
return parseInt ( ua.substring ( msie+5, ua.indexOf ( ".", msie ) ) )
else
return 0 // is other browser
}

var RunningNav4 = (Netscapeversion() >= 4)
function Netscapeversion() {
if (window.navigator.appName != "Netscape") {
return 0
} else {
return parseInt(window.navigator.appVersion.substring(0, 1))
}
}

var DHTMLbrowser = (RunningIE4 | RunningNav4) 


if (! DHTMLbrowser) {
  alert("Sorry, this page will only work in Navigator 4.0, IE 4.0 or later")
  history.go(-1)
}