Index: src/OFXMLElement.m
==================================================================
--- src/OFXMLElement.m
+++ src/OFXMLElement.m
@@ -316,10 +316,18 @@
 
 		attributes = [[attributesElement objectByDeserializing] copy];
 		namespaces = [[namespacesElement objectByDeserializing] copy];
 		children = [[childrenElement objectByDeserializing] copy];
 
+		if (namespaces == nil)
+			namespaces = [[OFMutableDictionary alloc] init];
+
+		[namespaces setObject: @"xml"
+			       forKey: @"http://www.w3.org/XML/1998/namespace"];
+		[namespaces setObject: @"xmlns"
+			       forKey: @"http://www.w3.org/2000/xmlns/"];
+
 		if (name == nil)
 			@throw [OFInvalidArgumentException
 			    exceptionWithClass: isa
 				      selector: _cmd];
 
@@ -712,17 +720,26 @@
 		[element addChild: attributesElement];
 	}
 
 	if (namespaces != nil) {
 		OFXMLElement *namespacesElement;
+		OFMutableDictionary *namespacesCopy =
+		    [[namespaces mutableCopy] autorelease];
 
-		namespacesElement =
-		    [OFXMLElement elementWithName: @"namespaces"
-					namespace: OF_SERIALIZATION_NS];
-		[namespacesElement addChild:
-		    [namespaces XMLElementBySerializing]];
-		[element addChild: namespacesElement];
+		[namespacesCopy removeObjectForKey:
+		    @"http://www.w3.org/XML/1998/namespace"];
+		[namespacesCopy removeObjectForKey:
+		    @"http://www.w3.org/2000/xmlns/"];
+
+		if ([namespacesCopy count] > 0) {
+			namespacesElement =
+			    [OFXMLElement elementWithName: @"namespaces"
+						namespace: OF_SERIALIZATION_NS];
+			[namespacesElement addChild:
+			    [namespacesCopy XMLElementBySerializing]];
+			[element addChild: namespacesElement];
+		}
 	}
 
 	if (children != nil) {
 		OFXMLElement *childrenElement;
 

Index: tests/serialization.xml
==================================================================
--- tests/serialization.xml
+++ tests/serialization.xml
@@ -31,46 +31,13 @@
         <OFString>Hello</OFString>
         <OFString>Wo&#xD;ld!
 How are you?</OFString>
         <OFURL>https://webkeks.org/</OFURL>
         <OFXMLElement name='x'>
-          <namespaces>
-            <OFMutableDictionary>
-              <key>
-                <OFString>http://www.w3.org/2000/xmlns/</OFString>
-              </key>
-              <object>
-                <OFString>xmlns</OFString>
-              </object>
-              <key>
-                <OFString>http://www.w3.org/XML/1998/namespace</OFString>
-              </key>
-              <object>
-                <OFString>xml</OFString>
-              </object>
-            </OFMutableDictionary>
-          </namespaces>
           <children>
             <OFMutableArray>
-              <OFXMLElement name='y'>
-                <namespaces>
-                  <OFMutableDictionary>
-                    <key>
-                      <OFString>http://www.w3.org/2000/xmlns/</OFString>
-                    </key>
-                    <object>
-                      <OFString>xmlns</OFString>
-                    </object>
-                    <key>
-                      <OFString>http://www.w3.org/XML/1998/namespace</OFString>
-                    </key>
-                    <object>
-                      <OFString>xml</OFString>
-                    </object>
-                  </OFMutableDictionary>
-                </namespaces>
-              </OFXMLElement>
+              <OFXMLElement name='y'/>
               <OFXMLCDATA><![CDATA[<]]></OFXMLCDATA>
             </OFMutableArray>
           </children>
         </OFXMLElement>
         <OFSet>