More perl sendxmpp config compatibility.

main.go

@@ -217,8 +217,18 @@ func main() {
 	// If no server part is specified in the username but a server is specified
 	// just assume the server is identical to the server part and hope for the
 	// best. This is for compatibility with the old perl sendxmpp config files.
+	var serverpart string
 	if !strings.Contains(user, "@") && server != "" {
-		user = user + "@" + server
+		// Remove port if server contains it.
+		if strings.Contains(server, ":") {
+			serverpart, _, err = net.SplitHostPort(server)
+			if err != nil {
+				log.Fatal(err)
+			}
+		} else {
+			serverpart = server
+		}
+		user = user + "@" + serverpart
 	}
 
 	switch {