diff --git a/smack-core/src/main/java/org/jivesoftware/smack/packet/Packet.java b/smack-core/src/main/java/org/jivesoftware/smack/packet/Packet.java
index 04676d078..0bc1c2194 100644
--- a/smack-core/src/main/java/org/jivesoftware/smack/packet/Packet.java
+++ b/smack-core/src/main/java/org/jivesoftware/smack/packet/Packet.java
@@ -36,6 +36,9 @@ import java.util.concurrent.atomic.AtomicLong;
  */
 public abstract class Packet {
 
+    public static final String TEXT = "text";
+    public static final String ITEM = "item";
+
     protected static final String DEFAULT_LANGUAGE =
             java.util.Locale.getDefault().getLanguage().toLowerCase(Locale.US);
 
diff --git a/smack-core/src/main/java/org/jivesoftware/smack/packet/RosterPacket.java b/smack-core/src/main/java/org/jivesoftware/smack/packet/RosterPacket.java
index 4822d1ad0..cddff51ad 100644
--- a/smack-core/src/main/java/org/jivesoftware/smack/packet/RosterPacket.java
+++ b/smack-core/src/main/java/org/jivesoftware/smack/packet/RosterPacket.java
@@ -17,10 +17,14 @@
 
 package org.jivesoftware.smack.packet;
 
-import org.jivesoftware.smack.util.StringUtils;
 import org.jivesoftware.smack.util.XmlStringBuilder;
 
-import java.util.*;
+import java.util.ArrayList;
+import java.util.Collection;
+import java.util.Collections;
+import java.util.List;
+import java.util.Locale;
+import java.util.Set;
 import java.util.concurrent.CopyOnWriteArraySet;
 
 /**
@@ -66,7 +70,8 @@ public class RosterPacket extends IQ {
         }
     }
 
-    public CharSequence getChildElementXML() {
+    @Override
+    public XmlStringBuilder getChildElementXML() {
         XmlStringBuilder buf = new XmlStringBuilder();
         buf.halfOpenElement("query");
         buf.xmlnsAttribute("jabber:iq:roster");
@@ -96,6 +101,8 @@ public class RosterPacket extends IQ {
      */
     public static class Item {
 
+        public static final String GROUP = "group";
+
         private String user;
         private String name;
         private ItemType itemType;
@@ -207,24 +214,19 @@ public class RosterPacket extends IQ {
             groupNames.remove(groupName);
         }
 
-        public String toXML() {
-            StringBuilder buf = new StringBuilder();
-            buf.append("<item jid=\"").append(StringUtils.escapeForXML(user)).append("\"");
-            if (name != null) {
-                buf.append(" name=\"").append(StringUtils.escapeForXML(name)).append("\"");
-            }
-            if (itemType != null) {
-                buf.append(" subscription=\"").append(itemType).append("\"");
-            }
-            if (itemStatus != null) {
-                buf.append(" ask=\"").append(itemStatus).append("\"");
-            }
-            buf.append(">");
+        public XmlStringBuilder toXML() {
+            XmlStringBuilder xml = new XmlStringBuilder();
+            xml.halfOpenElement(Packet.ITEM).attribute("jid", user);
+            xml.optAttribute("name", name);
+            xml.optAttribute("subscription", itemType);
+            xml.optAttribute("ask", itemStatus);
+            xml.rightAngelBracket();
+
             for (String groupName : groupNames) {
-                buf.append("<group>").append(StringUtils.escapeForXML(groupName)).append("</group>");
+                xml.openElement(GROUP).escape(groupName).closeElement(GROUP);
             }
-            buf.append("</item>");
-            return buf.toString();
+            xml.closeElement(Packet.ITEM);
+            return xml;
         }
 
         @Override
diff --git a/smack-core/src/main/java/org/jivesoftware/smack/packet/XMPPError.java b/smack-core/src/main/java/org/jivesoftware/smack/packet/XMPPError.java
index a11c98d32..b4fefd171 100644
--- a/smack-core/src/main/java/org/jivesoftware/smack/packet/XMPPError.java
+++ b/smack-core/src/main/java/org/jivesoftware/smack/packet/XMPPError.java
@@ -23,6 +23,8 @@ import java.util.List;
 import java.util.Locale;
 import java.util.Map;
 
+import org.jivesoftware.smack.util.XmlStringBuilder;
+
 /**
  * Represents a XMPP error sub-packet. Typically, a server responds to a request that has
  * problems by sending the packet back and including an error packet. Each error has a type,
@@ -60,6 +62,9 @@ import java.util.Map;
  */
 public class XMPPError {
 
+    public static final String NAMESPACE = "urn:ietf:params:xml:ns:xmpp-stanzas";
+    public static final String ERROR = "error";
+
     private final Type type;
     private final String condition;
     private String message;
@@ -153,29 +158,30 @@ public class XMPPError {
      *
      * @return the error as XML.
      */
-    public CharSequence toXML() {
-        StringBuilder buf = new StringBuilder();
-        buf.append("<error");
-        if (type != null) {
-            buf.append(" type=\"");
-            buf.append(type.name().toLowerCase(Locale.US));
-            buf.append("\"");
-        }
-        buf.append(">");
+    public XmlStringBuilder toXML() {
+        XmlStringBuilder xml = new XmlStringBuilder();
+        xml.halfOpenElement(ERROR);
+        xml.optAttribute("type", type.name().toLowerCase(Locale.US));
+        xml.rightAngelBracket();
+
         if (condition != null) {
-            buf.append("<").append(condition);
-            buf.append(" xmlns=\"urn:ietf:params:xml:ns:xmpp-stanzas\"/>");
+            xml.halfOpenElement(condition);
+            xml.xmlnsAttribute(NAMESPACE);
+            xml.closeEmptyElement();
         }
         if (message != null) {
-            buf.append("<text xml:lang=\"en\" xmlns=\"urn:ietf:params:xml:ns:xmpp-stanzas\">");
-            buf.append(message);
-            buf.append("</text>");
+            xml.halfOpenElement(Packet.TEXT);
+            xml.xmllangAttribute("en");
+            xml.xmlnsAttribute(NAMESPACE);
+            xml.rightAngelBracket();
+            xml.escape(message);
+            xml.closeElement(Packet.TEXT);
         }
         for (PacketExtension element : this.getExtensions()) {
-            buf.append(element.toXML());
+            xml.append(element.toXML());
         }
-        buf.append("</error>");
-        return buf.toString();
+        xml.closeElement(ERROR);
+        return xml;
     }
 
     public String toString() {
diff --git a/smack-core/src/main/java/org/jivesoftware/smack/util/PacketParserUtils.java b/smack-core/src/main/java/org/jivesoftware/smack/util/PacketParserUtils.java
index 64125e00b..cd2926585 100644
--- a/smack-core/src/main/java/org/jivesoftware/smack/util/PacketParserUtils.java
+++ b/smack-core/src/main/java/org/jivesoftware/smack/util/PacketParserUtils.java
@@ -779,7 +779,7 @@ public class PacketParserUtils {
             String namespace = parser.getNamespace();
             if (StreamError.NAMESPACE.equals(namespace)) {
                 String name = parser.getName();
-                if (name.equals("text") && !parser.isEmptyElementTag()) {
+                if (name.equals(Packet.TEXT) && !parser.isEmptyElementTag()) {
                     parser.next();
                     text = parser.getText();
                 }
@@ -822,7 +822,7 @@ public class PacketParserUtils {
         while (!done) {
             int eventType = parser.next();
             if (eventType == XmlPullParser.START_TAG) {
-                if (parser.getName().equals("text")) {
+                if (parser.getName().equals(Packet.TEXT)) {
                     message = parser.nextText();
                 }
                 else {