diff --git a/smack-core/src/main/java/org/jivesoftware/smack/AbstractXMPPConnection.java b/smack-core/src/main/java/org/jivesoftware/smack/AbstractXMPPConnection.java
index 377d53c0c..a421d6cd1 100644
--- a/smack-core/src/main/java/org/jivesoftware/smack/AbstractXMPPConnection.java
+++ b/smack-core/src/main/java/org/jivesoftware/smack/AbstractXMPPConnection.java
@@ -2229,7 +2229,7 @@ public abstract class AbstractXMPPConnection implements XMPPConnection {
         }
     }
 
-    protected void sendStreamOpen() throws NotConnectedException, InterruptedException {
+    protected final void sendStreamOpen() throws NotConnectedException, InterruptedException {
         // If possible, provide the receiving entity of the stream open tag, i.e. the server, as much information as
         // possible. The 'to' attribute is *always* available. The 'from' attribute if set by the user and no external
         // mechanism is used to determine the local entity (user). And the 'id' attribute is available after the first
@@ -2241,12 +2241,17 @@ public abstract class AbstractXMPPConnection implements XMPPConnection {
             from = XmppStringUtils.completeJidFrom(localpart, to);
         }
         String id = getStreamId();
+        String lang = config.getXmlLang();
 
-        StreamOpen streamOpen = new StreamOpen(to, from, id, config.getXmlLang(), StreamOpen.StreamContentNamespace.client);
+        AbstractStreamOpen streamOpen = getStreamOpen(to, from, id, lang);
         sendNonza(streamOpen);
         updateOutgoingStreamXmlEnvironmentOnStreamOpen(streamOpen);
     }
 
+    protected AbstractStreamOpen getStreamOpen(CharSequence to, CharSequence from, String id, String lang) {
+        return new StreamOpen(to, from, id, lang);
+    }
+
     protected void updateOutgoingStreamXmlEnvironmentOnStreamOpen(AbstractStreamOpen streamOpen) {
         XmlEnvironment.Builder xmlEnvironmentBuilder = XmlEnvironment.builder();
         xmlEnvironmentBuilder.with(streamOpen);
diff --git a/smack-core/src/main/java/org/jivesoftware/smack/c2s/ModularXmppClientToServerConnection.java b/smack-core/src/main/java/org/jivesoftware/smack/c2s/ModularXmppClientToServerConnection.java
index e404795db..191dd32e4 100644
--- a/smack-core/src/main/java/org/jivesoftware/smack/c2s/ModularXmppClientToServerConnection.java
+++ b/smack-core/src/main/java/org/jivesoftware/smack/c2s/ModularXmppClientToServerConnection.java
@@ -560,6 +560,12 @@ public final class ModularXmppClientToServerConnection extends AbstractXMPPConne
         waitForConditionOrThrowConnectionException(() -> featuresReceived, waitFor);
     }
 
+    @Override
+    protected AbstractStreamOpen getStreamOpen(CharSequence to, CharSequence from, String id, String lang) {
+        StreamOpenAndCloseFactory streamOpenAndCloseFactory = activeTransport.getStreamOpenAndCloseFactory();
+        return streamOpenAndCloseFactory.createStreamOpen(to, from, id, lang);
+    }
+
     protected void newStreamOpenWaitForFeaturesSequence(String waitFor) throws InterruptedException,
                     SmackException, XMPPException {
         prepareToWaitForFeaturesReceived();
diff --git a/smack-core/src/main/java/org/jivesoftware/smack/packet/AbstractStreamOpen.java b/smack-core/src/main/java/org/jivesoftware/smack/packet/AbstractStreamOpen.java
index 36f0dc760..1b6a3d1e0 100644
--- a/smack-core/src/main/java/org/jivesoftware/smack/packet/AbstractStreamOpen.java
+++ b/smack-core/src/main/java/org/jivesoftware/smack/packet/AbstractStreamOpen.java
@@ -1,6 +1,6 @@
 /**
  *
- * Copyright 2020 Aditya Borikar
+ * Copyright 2020 Florian Schmaus, Aditya Borikar
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -60,6 +60,10 @@ public abstract class AbstractStreamOpen implements Nonza {
      */
     protected final String contentNamespace;
 
+    public AbstractStreamOpen(CharSequence to, CharSequence from, String id, String lang) {
+        this(to, from, id, lang, StreamContentNamespace.client);
+    }
+
     public AbstractStreamOpen(CharSequence to, CharSequence from, String id, String lang, StreamContentNamespace ns) {
         this.to = StringUtils.maybeToString(to);
         this.from = StringUtils.maybeToString(from);
diff --git a/smack-core/src/main/java/org/jivesoftware/smack/packet/StreamOpen.java b/smack-core/src/main/java/org/jivesoftware/smack/packet/StreamOpen.java
index f4b59db4b..959adc1fa 100644
--- a/smack-core/src/main/java/org/jivesoftware/smack/packet/StreamOpen.java
+++ b/smack-core/src/main/java/org/jivesoftware/smack/packet/StreamOpen.java
@@ -1,6 +1,6 @@
 /**
  *
- * Copyright © 2014-2019 Florian Schmaus
+ * Copyright © 2014-2020 Florian Schmaus
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -33,6 +33,10 @@ public final class StreamOpen extends AbstractStreamOpen {
         this(to, from, id, "en", StreamContentNamespace.client);
     }
 
+    public StreamOpen(CharSequence to, CharSequence from, String id, String lang) {
+        super(to, from, id, lang);
+    }
+
     public StreamOpen(CharSequence to, CharSequence from, String id, String lang, StreamContentNamespace ns) {
         super(to, from, id, lang, ns);
     }
diff --git a/smack-core/src/main/java/org/jivesoftware/smack/util/XmlStringBuilder.java b/smack-core/src/main/java/org/jivesoftware/smack/util/XmlStringBuilder.java
index c483db913..50e27e072 100644
--- a/smack-core/src/main/java/org/jivesoftware/smack/util/XmlStringBuilder.java
+++ b/smack-core/src/main/java/org/jivesoftware/smack/util/XmlStringBuilder.java
@@ -1,6 +1,6 @@
 /**
  *
- * Copyright 2014-2019 Florian Schmaus
+ * Copyright 2014-2020 Florian Schmaus
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -24,7 +24,6 @@ import java.util.Date;
 import java.util.List;
 
 import org.jivesoftware.smack.packet.Element;
-import org.jivesoftware.smack.packet.ExtensionElement;
 import org.jivesoftware.smack.packet.FullyQualifiedElement;
 import org.jivesoftware.smack.packet.NamedElement;
 import org.jivesoftware.smack.packet.XmlEnvironment;
@@ -43,7 +42,7 @@ public class XmlStringBuilder implements Appendable, CharSequence, Element {
         effectiveXmlEnvironment = null;
     }
 
-    public XmlStringBuilder(ExtensionElement pe) {
+    public XmlStringBuilder(FullyQualifiedElement pe) {
         this(pe, null);
     }
 
diff --git a/smack-extensions/src/main/java/org/jivesoftware/smackx/jingle/element/JingleReason.java b/smack-extensions/src/main/java/org/jivesoftware/smackx/jingle/element/JingleReason.java
index 91c909aba..a7f1364a4 100644
--- a/smack-extensions/src/main/java/org/jivesoftware/smackx/jingle/element/JingleReason.java
+++ b/smack-extensions/src/main/java/org/jivesoftware/smackx/jingle/element/JingleReason.java
@@ -1,6 +1,6 @@
 /**
  *
- * Copyright 2017-2019 Florian Schmaus
+ * Copyright 2017-2020 Florian Schmaus
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -151,7 +151,7 @@ public class JingleReason implements FullyQualifiedElement {
 
         @Override
         public XmlStringBuilder toXML(org.jivesoftware.smack.packet.XmlEnvironment enclosingNamespace) {
-            XmlStringBuilder xml = new XmlStringBuilder(this);
+            XmlStringBuilder xml = new XmlStringBuilder(this, enclosingNamespace);
             xml.rightAngleBracket();
 
             xml.openElement(reason.asString);