Security warning when using the "longpoling" connection with SignalR while in a secure connection (HTTPS) | IE8

There is only one problem: I just get a warning "Securty Waring"in the IE 8SignalR chat application, and in HTTPS

I use longpollingas a transport type when in IE8. It works fine in all other IE browsers.

self.Connect = function () {
     hubConn.start({ transport: 'longPolling' }).done(function (result) {
                ///--
     }).fail(function (error) {
                ///--
         alert("error" + error);
     });
}

When I tried fiddler, a security warning appeared with the ajax signalr signal, as shown below.