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

// 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)))
	is_major = parseInt(is_minor);
}
var is_getElementById	= (document.getElementById) ? "true" : "false";
var is_getElementsByTagName = (document.getElementsByTagName) ? "true" : "false";
var is_documentElement = (document.documentElement) ? "true" : "false";
var isKonqueror = (agt.indexOf("konqueror") != -1);
var isSafari = (agt.indexOf("safari") != -1);
var is_gecko = !isKonqueror && !isSafari && (agt.indexOf("gecko/") != -1);
var is_gver  = 0;
if (is_gecko) is_gver=navigator.productSub;
var is_firebird = ((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=="Firebird"));
var is_firefox = ((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=="Firefox"));
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")));
var is_moz5up = (is_moz && (is_major >= 5));
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);
}
if (is_firebird) {
	var is_fb_ver = (navigator.vendorSub)?navigator.vendorSub:0;
	if(!(is_fb_ver)) {
		is_fb_ver = agt.indexOf('rv:');
		is_fb_ver = agt.substring(is_moz_ver+3);
		is_paren = is_fb_ver.indexOf(')');
		is_fb_ver = is_fb_ver.substring(0,is_paren);
	}
	is_fb_ver;
}
if (is_firefox) {
	var is_ff_ver = (navigator.vendorSub)?navigator.vendorSub:0;
	if(!(is_ff_ver)) {
		is_ff_ver = agt.indexOf('rv:');
		is_ff_ver = agt.substring(is_moz_ver+3);
		is_paren	= is_ff_ver.indexOf(')');
		is_ff_ver = is_ff_ver.substring(0,is_paren);
	}
	is_ff_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_moz)));
// Netscape6 is mozilla/5 + Netscape6/6.0!!!
// Mozilla/5.0 (Windows; U; Win98; en-US; m18) Gecko/20001108 Netscape6/6.0
// Changed this to use navigator.vendor/vendorSub - dmr 060502	
// var nav6Pos = agt.indexOf('netscape6');
// if (nav6Pos !=-1) {
if ((navigator.vendor) && ((navigator.vendor=="Netscape6")||(navigator.vendor=="Netscape")) && (is_nav)) {
	is_major = parseInt(navigator.vendorSub);
	is_minor = parseFloat(navigator.vendorSub);
}
var is_opera = (agt.indexOf("opera") != -1);
var is_opera2 = (agt.indexOf("opera 2") != -1 || agt.indexOf("opera/2") != -1);
var is_opera3 = (agt.indexOf("opera 3") != -1 || agt.indexOf("opera/3") != -1);
var is_opera4 = (agt.indexOf("opera 4") != -1 || agt.indexOf("opera/4") != -1);
var is_opera5 = (agt.indexOf("opera 5") != -1 || agt.indexOf("opera/5") != -1);
var is_opera6 = (agt.indexOf("opera 6") != -1 || agt.indexOf("opera/6") != -1);
var is_opera7 = (agt.indexOf("opera 7") != -1 || agt.indexOf("opera/7") != -1);
var is_opera5up = (is_opera && !is_opera2 && !is_opera3 && !is_opera4);
var is_opera6up = (is_opera && !is_opera2 && !is_opera3 && !is_opera4 && !is_opera5);
var is_opera7up = (is_opera && !is_opera2 && !is_opera3 && !is_opera4 && !is_opera5 && !is_opera6);
var is_nav2 = (is_nav && (is_major == 2));
var is_nav3 = (is_nav && (is_major == 3));
var is_nav4 = (is_nav && (is_major == 4));
var is_nav4up = (is_nav && is_minor >= 4);
var is_navonly = (is_nav && ((agt.indexOf(";nav") != -1) || (agt.indexOf("; nav") != -1)) );
var is_nav6	= (is_nav && is_major==6);
var is_nav6up = (is_nav && is_minor >= 6);
var is_nav5	= (is_nav && is_major == 5 && !is_nav6);
var is_nav5up = (is_nav && is_minor >= 5);
var is_nav7	= (is_nav && is_major == 7);
var is_nav7up = (is_nav && is_minor >= 7);
var is_ie = ((iePos!=-1) && (!is_opera));
var is_ie3 = (is_ie && (is_major < 4));
var is_ie4 = (is_ie && is_major == 4);
var is_ie4up = (is_ie && is_minor >= 4);
var is_ie5 = (is_ie && is_major == 5);
var is_ie5up = (is_ie && is_minor >= 5);
var is_ie5_5 = (is_ie && (agt.indexOf("msie 5.5") !=-1));
var is_ie5_5up =(is_ie && is_minor >= 5.5);
var is_ie6 = (is_ie && is_major == 6);
var is_ie6up = (is_ie && is_minor >= 6);
// KNOWN BUG: On AOL4, returns false if IE3 is embedded browser
// or if this is the first browser window opened.  Thus the
// variables is_aol, is_aol3, and is_aol4 aren't 100% reliable.
var is_aol = (agt.indexOf("aol") != -1);
var is_aol3 = (is_aol && is_ie3);
var is_aol4 = (is_aol && is_ie4);
var is_aol5  = (agt.indexOf("aol 5") != -1);
var is_aol6  = (agt.indexOf("aol 6") != -1);
var is_aol7  = ((agt.indexOf("aol 7")!=-1) || (agt.indexOf("aol7")!=-1));
var is_webtv = (agt.indexOf("webtv") != -1);
var is_TVNavigator = ((agt.indexOf("navio") != -1) || (agt.indexOf("navio_aoltv") != -1)); 
var is_AOLTV = is_TVNavigator;
var is_hotjava = (agt.indexOf("hotjava") != -1);
var is_hotjava3 = (is_hotjava && (is_major == 3));
var is_hotjava3up = (is_hotjava && (is_major >= 3));