gistfile1.txt

        var Browser = {
            Version: function() {
                var version = 999; // we assume a sane browser
                if (navigator.appVersion.indexOf("MSIE") != -1)
                // bah, IE again, lets downgrade version number
                    version = parseFloat(navigator.appVersion.split("MSIE")[1]);
                return version;
            },
            DocumentVersion: function () {
                var version = 999; // we assume a sane browser
                if (navigator.appVersion.indexOf("MSIE") != -1) {
                    var documentVersion = document.documentMode;
                    if (documentVersion !== undefined) {
                        version = documentVersion
                    } else {
                        version = 1; // documentMode included from IE8>=, just fail older browser!
                    }
                }
                return version;
            }
        };
        if (Browser.Version() < 9) {
            alert("Your version of Internet Explorer is too old to run Netmap. Please upgrade to IE9 or make sure DocumentMode is set to 9 or newer");
        } else if (Browser.DocumentVersion() < 9) {
            alert("Netmap requires Internet Explorer to have DocumentMode 9 or newer!");
        }