Index: library/Zend/XmlRpc/Server.php
===================================================================
--- library/Zend/XmlRpc/Server.php	(revision 8704)
+++ library/Zend/XmlRpc/Server.php	(working copy)
@@ -168,7 +168,8 @@
         'time'             => 'dateTime.iso8601',
         'array'            => 'array',
         'struct'           => 'struct',
-        'null'             => 'void',
+        'null'             => 'nil',
+        'nil'              => 'nil',
         'void'             => 'void',
         'mixed'            => 'struct'
     );
Index: library/Zend/XmlRpc/Value.php
===================================================================
--- library/Zend/XmlRpc/Value.php	(revision 8704)
+++ library/Zend/XmlRpc/Value.php	(working copy)
@@ -43,6 +43,9 @@
 /** Zend_XmlRpc_Value_String */
 require_once 'Zend/XmlRpc/Value/String.php';
 
+/** Zend_XmlRpc_Value_Nil */
+require_once 'Zend/XmlRpc/Value/Nil.php';
+
 /** Zend_XmlRpc_Value_Collection */
 require_once 'Zend/XmlRpc/Value/Collection.php';
 
@@ -115,6 +118,7 @@
     const XMLRPC_TYPE_BASE64   = 'base64';
     const XMLRPC_TYPE_ARRAY    = 'array';
     const XMLRPC_TYPE_STRUCT   = 'struct';
+    const XMLRPC_TYPE_NIL      = 'nil';
 
 
     /**
@@ -208,6 +212,9 @@
             case self::XMLRPC_TYPE_BASE64:
                 return new Zend_XmlRpc_Value_Base64($value);
 
+            case self::XMLRPC_TYPE_NIL:
+                return new Zend_XmlRpc_Value_Nil();
+
             case self::XMLRPC_TYPE_DATETIME:
                 return new Zend_XmlRpc_Value_DateTime($value);
 
@@ -262,6 +269,10 @@
             case 'boolean':
                 return new Zend_XmlRpc_Value_Boolean($value);
 
+            case 'NULL':
+            case 'null':
+                return new Zend_XmlRpc_Value_Nil();
+
             case 'string':
                 // Fall through to the next case
             default:
@@ -319,6 +330,9 @@
             case self::XMLRPC_TYPE_BASE64:    // The value should already be base64 encoded
                 $xmlrpc_val = new Zend_XmlRpc_Value_Base64($value ,true);
                 break;
+            case self::XMLRPC_TYPE_NIL:    // The value should always be NULL
+                $xmlrpc_val = new Zend_XmlRpc_Value_Nil();
+                break;
             case self::XMLRPC_TYPE_ARRAY:
                 // If the XML is valid, $value must be an SimpleXML element and contain the <data> tag
                 if (!$value instanceof SimpleXMLElement) {
Index: library/Zend/XmlRpc/Value/Nil.php
===================================================================
--- library/Zend/XmlRpc/Value/Nil.php	(revision 0)
+++ library/Zend/XmlRpc/Value/Nil.php	(revision 0)
@@ -0,0 +1,78 @@
+<?php
+/**
+ * Zend Framework
+ *
+ * LICENSE
+ *
+ * This source file is subject to the new BSD license that is bundled
+ * with this package in the file LICENSE.txt.
+ * It is also available through the world-wide-web at this URL:
+ * http://framework.zend.com/license/new-bsd
+ * If you did not receive a copy of the license and are unable to
+ * obtain it through the world-wide-web, please send an email
+ * to license@zend.com so we can send you a copy immediately.
+ *
+ * @category   Zend
+ * @package    Zend_XmlRpc
+ * @subpackage Value
+ * @copyright  Copyright (c) 2005-2008 Zend Technologies USA Inc. (http://www.zend.com)
+ * @license    http://framework.zend.com/license/new-bsd     New BSD License
+ */
+
+
+/**
+ * Zend_XmlRpc_Value_Scalar
+ */
+require_once 'Zend/XmlRpc/Value/Scalar.php';
+
+
+/**
+ * @category   Zend
+ * @package    Zend_XmlRpc
+ * @subpackage Value
+ * @copyright  Copyright (c) 2005-2008 Zend Technologies USA Inc. (http://www.zend.com)
+ * @license    http://framework.zend.com/license/new-bsd     New BSD License
+ */
+class Zend_XmlRpc_Value_Nil extends Zend_XmlRpc_Value_Scalar
+{
+
+    /**
+     * Set the value of a nil native type
+     *
+     */
+    public function __construct()
+    {
+        $this->_type = self::XMLRPC_TYPE_NIL;
+        $this->_value = null;
+    }
+
+    /**
+     * Return the value of this object, convert the XML-RPC native nill value into a PHP NULL
+     *
+     * @return null
+     */
+    public function getValue()
+    {
+        return null;
+    }
+
+    /**
+     * Return the XML code representing the nil
+     * 
+     * @return string
+     */
+    public function saveXML()
+    {
+        if (! $this->_as_xml) {   // The XML was not generated yet
+            $dom   = new DOMDocument('1.0', 'UTF-8');
+            $value = $dom->appendChild($dom->createElement('value'));
+            $type  = $value->appendChild($dom->createElement($this->_type));
+
+            $this->_as_dom = $value;
+            $this->_as_xml = $this->_stripXmlDeclaration($dom);
+        }
+
+        return $this->_as_xml;
+    }
+}
+
Index: tests/Zend/XmlRpc/ValueTest.php
===================================================================
--- tests/Zend/XmlRpc/ValueTest.php	(revision 8704)
+++ tests/Zend/XmlRpc/ValueTest.php	(working copy)
@@ -18,6 +18,7 @@
 require_once 'Zend/XmlRpc/Value/Double.php';
 require_once 'Zend/XmlRpc/Value/Integer.php';
 require_once 'Zend/XmlRpc/Value/String.php';
+require_once 'Zend/XmlRpc/Value/Nil.php';
 require_once 'Zend/XmlRpc/Value/Struct.php';
 
 /**
@@ -179,6 +180,37 @@
         $this->assertEquals($this->wrapXml($xml), $val->saveXML());        
     }
 
+    //Nil
+
+    public function testFactoryAutodetectsNil()
+    {
+        $val = Zend_XmlRpc_Value::getXmlRpcValue(NULL);
+        $this->assertXmlRpcType('nil', $val);
+    }
+
+    public function testMarshalNilFromNative()
+    {
+        $native = NULL;
+        $val = Zend_XmlRpc_Value::getXmlRpcValue($native, 
+                                    Zend_XmlRpc_Value::XMLRPC_TYPE_NIL);
+
+        $this->assertXmlRpcType('nil', $val);
+        $this->assertSame($native, $val->getValue());
+    }
+
+    public function testMarshalNilFromXmlRpc()
+    {
+        $xml = '<value><nil/></value>';
+        $val = Zend_XmlRpc_Value::getXmlRpcValue($xml, 
+                                    Zend_XmlRpc_Value::XML_STRING);
+
+        $this->assertXmlRpcType('nil', $val);
+        $this->assertEquals('nil', $val->getType());
+        $this->assertSame(NULL, $val->getValue());
+        $this->assertType('DomElement', $val->getAsDOM());
+        $this->assertEquals($this->wrapXml($xml), $val->saveXML());
+    }
+
     // Array
 
     public function testFactoryAutodetectsArray()