// convert all characters to lowercase to simplify testing
    var agt=navigator.userAgent.toLowerCase();
    var appVer = navigator.appVersion.toLowerCase();

    // *** BROWSER VERSION ***

    var is_ff = (agt.indexOf("firefox") != -1);

    var is_minor = parseFloat(appVer);
    var is_major = parseInt(is_minor);

    var is_opera = (agt.indexOf("opera") != -1);
    var is_opera72 = (agt.indexOf("opera 7.2") != -1 || agt.indexOf("opera/7.2") != -1); // new 021205- dmr
    var is_opera75 = (agt.indexOf("opera 7.5") != -1 || agt.indexOf("opera/7.5") != -1); // new 021205- dmr

    var is_opera720up = (is_opera && (is_opera72 || is_opera75)); // new021205 -- dmr

    // Note: On IE, start of appVersion return 3 or 4
    // which supposedly is the version of Netscape it is compatible with.
    // So we look for the real version further on in the string

    var iePos  = appVer.indexOf('msie');
    if (iePos !=-1) {
       is_minor = parseFloat(appVer.substring(iePos+5,appVer.indexOf(';',iePos)));  //added missing ; - 030617 - bdn
       is_major = parseInt(is_minor);
    }

    // ditto Konqueror
    var is_konq = false;
    var kqPos   = agt.indexOf('konqueror');
    if (kqPos !=-1) {
       is_konq  = true;
       is_minor = parseFloat(agt.substring(kqPos+10,agt.indexOf(';',kqPos)));
       is_major = parseInt(is_minor);
    }

    var is_safari = ((agt.indexOf('safari')!=-1)&&(agt.indexOf('mac')!=-1))?true:false;
    var is_khtml  = (is_safari || is_konq);

    var is_gecko = ((!is_khtml)&&(navigator.product)&&(navigator.product.toLowerCase()=="gecko"))?true:false;
    var is_gver  = 0;
    if (is_gecko) is_gver=navigator.productSub;

    var is_moz   = ((agt.indexOf('mozilla/5')!=-1) && (agt.indexOf('spoofer')==-1) &&
                    (agt.indexOf('compatible')==-1) && (agt.indexOf('opera')==-1)  &&
                    (agt.indexOf('webtv')==-1) && (agt.indexOf('hotjava')==-1)     &&
                    (is_gecko) &&
                    ((navigator.vendor=="")||(navigator.vendor=="Mozilla")));
    if (is_moz) {
       var is_moz_ver = (navigator.vendorSub)?navigator.vendorSub:0;
       if(!(is_moz_ver)) {
           is_moz_ver = agt.indexOf('rv:');
           is_moz_ver = agt.substring(is_moz_ver+3);
           is_paren   = is_moz_ver.indexOf(')');
           is_moz_ver = is_moz_ver.substring(0,is_paren);
       }
       is_minor = is_moz_ver;
       is_major = parseInt(is_moz_ver);
    }

    var is_nav  = ((agt.indexOf('mozilla')!=-1) && (agt.indexOf('spoofer')==-1)
                && (agt.indexOf('compatible') == -1) && (agt.indexOf('opera')==-1)
                && (agt.indexOf('webtv')==-1) && (agt.indexOf('hotjava')==-1)
                && (!is_khtml) && (!(is_moz)));

    if ((navigator.vendor)&&
        ((navigator.vendor=="Netscape6")||(navigator.vendor=="Netscape"))&&
        (is_nav)) {
       is_major = parseInt(navigator.vendorSub);
       // here we need is_minor as a valid float for testing. We'll
       // revert to the actual content before printing the result.
       is_minor = parseFloat(navigator.vendorSub);
    }

    var is_nav7up = (is_nav && is_minor >= 7);

    var is_ie   = ((iePos!=-1) && (!is_opera) && (!is_khtml));
    var is_ie5up = (is_ie && is_minor >= 5);

// does browser check
// suppported browsers are IE 5+, FireFox, NS 7+, Opera 7.20+ and Mozilla
function doBrowserCheck() {	
	if(!(is_ie5up || is_ff || (is_nav7up || (is_nav && is_minor >= 6.2)) || (is_moz && is_major == 1) || is_opera720up || is_safari)){
		// browser not supported, redirect to support page
		document.location = "/dafiles/OCA/OptusHome/StaticFiles/HTML/support.html";
	}
}