function browserAllowed() {
	var agt = BrowserDetect.browser;
	var ver = BrowserDetect.version;
	if ((agt == "Explorer" && ver < 6) ||
		(agt == "Firefox" && ver < 3) ||
		(agt == "Safari" && ver < 3) ||
		(agt == "Chrome" && ver < 3) ||
		(agt == "Opera")
		) {
		return false;
	} else {
		return true;
	}
}


var BrowserDetect = {
	init: function () {
		this.browser = this.searchString(this.dataBrowser) || "An unknown browser";
		this.version = this.searchVersion(navigator.userAgent)
			|| this.searchVersion(navigator.appVersion)
			|| "an unknown version";
		this.versionString = this.searchVersionString(navigator.userAgent)
			|| this.searchVersionString(navigator.appVersion)
			|| "an unknown version";
		this.OS = this.searchString(this.dataOS) || "an unknown OS";
	},
	searchString: function (data) {
		for (var i=0;i<data.length;i++)	{
			var dataString = data[i].string;
			var dataProp = data[i].prop;
			this.versionSearchString = data[i].versionSearch || data[i].identity;
			if (dataString) {
				if (dataString.indexOf(data[i].subString) != -1)
					return data[i].identity;
			}
			else if (dataProp)
				return data[i].identity;
		}
	},
	searchVersion: function (dataString) {
		var index = dataString.indexOf(this.versionSearchString);
		if (index == -1) return;
		return parseFloat(dataString.substring(index+this.versionSearchString.length+1));
	},
	searchVersionString: function (dataString) {
		var index = dataString.indexOf(this.versionSearchString);
		if (index == -1) return;
		index += this.versionSearchString.length+1;
		// find first space after version string
		var posSpace = dataString.indexOf(" ", index);
		// find first semi-colon after version string
		var posSemi = dataString.indexOf(";", index);
		// find end of version string (defaults to end of string)
		var index2 = dataString.length;
		if (posSpace > -1 && posSpace < index2) {
			index2 = posSpace;
		}
		if (posSemi > -1 && posSemi < index2) {
			index2 = posSemi;
		}
		return dataString.substring(index, index2);
	},
	dataBrowser: [
		{
			string: navigator.userAgent,
			subString: "Chrome",
			identity: "Chrome"
		},
		{ 	string: navigator.userAgent,
			subString: "OmniWeb",
			versionSearch: "OmniWeb/",
			identity: "OmniWeb"
		},
		{
			string: navigator.vendor,
			subString: "Apple",
			identity: "Safari",
			versionSearch: "Version"
		},
		{
			prop: window.opera,
			identity: "Opera"
		},
		{
			string: navigator.vendor,
			subString: "iCab",
			identity: "iCab"
		},
		{
			string: navigator.vendor,
			subString: "KDE",
			identity: "Konqueror"
		},
		{
			string: navigator.userAgent,
			subString: "Firefox",
			identity: "Firefox"
		},
		{
			string: navigator.vendor,
			subString: "Camino",
			identity: "Camino"
		},
		{		// for newer Netscapes (6+)
			string: navigator.userAgent,
			subString: "Netscape",
			identity: "Netscape"
		},
		{
			string: navigator.userAgent,
			subString: "MSIE",
			identity: "Explorer",
			versionSearch: "MSIE"
		},
		{
			string: navigator.userAgent,
			subString: "Gecko",
			identity: "Mozilla",
			versionSearch: "rv"
		},
		{ 		// for older Netscapes (4-)
			string: navigator.userAgent,
			subString: "Mozilla",
			identity: "Netscape",
			versionSearch: "Mozilla"
		}
	],
	dataOS : [
		{
			string: navigator.platform,
			subString: "Win",
			identity: "Windows"
		},
		{
			string: navigator.platform,
			subString: "Mac",
			identity: "Mac"
		},
		{
			string: navigator.userAgent,
			subString: "iPhone",
			identity: "iPhone/iPod"
	    	},
		{
			string: navigator.userAgent,
			subString: "iPod",
			identity: "iPhone/iPod"
	    	},
		{
			string: navigator.userAgent,
			subString: "iPad",
			identity: "iPad"
	    	},
		{
			string: navigator.platform,
			subString: "Linux",
			identity: "Linux"
		}
	]

};
BrowserDetect.init();