Split on first @ instead of the last to get the domain (thx Sam)

connect.go

@@ -39,7 +39,7 @@ func connect(options xmpp.Options, directTLS bool) (*xmpp.Client, error) {
 	// Look up SRV records if server is not specified manually.
 	srvMixed := srvMixed{}
 	if options.Host == "" {
-		server := options.User[strings.LastIndex(options.User, "@")+1:]
+		server := options.User[strings.Index(options.User, "@")+1:]
 		// Look up xmpp-client SRV records.
 		if _, addrs, err := net.LookupSRV("xmpp-client", "tcp", server); err == nil {
 			if len(addrs) > 0 {

go-sendxmpp.go

@@ -308,14 +308,14 @@ func main() {
 
 	// Use ALPN
 	var tlsConfig tls.Config
-	tlsConfig.ServerName = user[strings.LastIndex(user, "@")+1:]
+	tlsConfig.ServerName = user[strings.Index(user, "@")+1:]
 	tlsConfig.NextProtos = append(tlsConfig.NextProtos, "xmpp-client")
 	tlsConfig.InsecureSkipVerify = *flagSkipVerify
 
 	// Set XMPP connection options.
 	options := xmpp.Options{
-		Host:        server,
-		User:        user,
+		Host: server,
+		User: user,
 		// TODO: Check whether the timeout is reasonable or maybe make
 		// it configurable
 		DialTimeout: 1 * time.Second,