diff --git a/firefox_addon/lib/main.js b/firefox_addon/lib/main.js
index 9f89cd4..41249cc 100644
--- a/firefox_addon/lib/main.js
+++ b/firefox_addon/lib/main.js
@@ -54,7 +54,7 @@ function debug(s)
 	console.log(s);
 }
 
-function on_sumbit()
+function on_sumbit(e)
 {
     var form = this;
     var fields = form.getElementsByTagName("input");
@@ -130,14 +130,25 @@ function on_sumbit()
 	    	r = this.responseText.split("\n");
 		debug("resp " + r);
 		protocol = r[0].split("=");
-		if (protocol[1] != "1")
+		if ((protocol.length == 2 && protocol[1] != "1" && protocol[1] != "gpass-1") || protocol.length != 2)
 		{
 		    ret = false;
-		    notifications.notify({
-			title: "gPasss",
-			text: "Protocol version not supported, please upgrade your addon",
-			data: "Protocol version not supported, please upgrade your addon",
-		    });
+		    if (protocol.length == 2 && protocol[1].startsWith("gpass"))
+		    {
+			notifications.notify({
+			    title: "gPasss",
+			    text: "Protocol version not supported, please upgrade your addon",
+			    data: "Protocol version not supported, please upgrade your addon",
+			});
+		    }
+		    else
+		    {
+			notifications.notify({
+			    title: "gPasss",
+			    text: "Error : It seems that it's not a gPass server",
+			    data: this.responseText,
+			});
+		    }
 		}
 		else
 		{
@@ -183,7 +194,11 @@ function on_sumbit()
 	    gPassRequest.setRequestHeader('Content-Type', 'application/x-www-form-urlencoded; charset=UTF-8');
 	    gPassRequest.send(keys);
 
-	    if (!ret) return ret;
+	    if (!ret)
+	    {
+		e.preventDefault();
+		return ret;
+	    }
 	}
     }
 }