diff -r 5b37998e522e -r 162c1de6545a web/lib/Zend/Pdf/Trailer.php
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/web/lib/Zend/Pdf/Trailer.php	Fri Mar 11 15:05:35 2011 +0100
@@ -0,0 +1,126 @@
+<?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_Pdf
+ * @copyright  Copyright (c) 2005-2010 Zend Technologies USA Inc. (http://www.zend.com)
+ * @license    http://framework.zend.com/license/new-bsd     New BSD License
+ * @version    $Id: Trailer.php 20096 2010-01-06 02:05:09Z bkarwin $
+ */
+
+
+/**
+ * PDF file trailer
+ *
+ * @package    Zend_Pdf
+ * @copyright  Copyright (c) 2005-2010 Zend Technologies USA Inc. (http://www.zend.com)
+ * @license    http://framework.zend.com/license/new-bsd     New BSD License
+ */
+abstract class Zend_Pdf_Trailer
+{
+    private static $_allowedKeys = array('Size', 'Prev', 'Root', 'Encrypt', 'Info', 'ID', 'Index', 'W', 'XRefStm', 'DocChecksum');
+
+    /**
+     * Trailer dictionary.
+     *
+     * @var Zend_Pdf_Element_Dictionary
+     */
+    private $_dict;
+
+    /**
+     * Check if key is correct
+     *
+     * @param string $key
+     * @throws Zend_Pdf_Exception
+     */
+    private function _checkDictKey($key)
+    {
+        if ( !in_array($key, self::$_allowedKeys) ) {
+            /** @todo Make warning (log entry) instead of an exception */
+            require_once 'Zend/Pdf/Exception.php';
+            throw new Zend_Pdf_Exception("Unknown trailer dictionary key: '$key'.");
+        }
+    }
+
+
+    /**
+     * Object constructor
+     *
+     * @param Zend_Pdf_Element_Dictionary $dict
+     */
+    public function __construct(Zend_Pdf_Element_Dictionary $dict)
+    {
+        $this->_dict   = $dict;
+
+        foreach ($this->_dict->getKeys() as $dictKey) {
+            $this->_checkDictKey($dictKey);
+        }
+    }
+
+    /**
+     * Get handler
+     *
+     * @param string $property
+     * @return mixed
+     */
+    public function __get($property)
+    {
+        return $this->_dict->$property;
+    }
+
+    /**
+     * Set handler
+     *
+     * @param string $property
+     * @param  mixed $value
+     */
+    public function __set($property, $value)
+    {
+        $this->_checkDictKey($property);
+        $this->_dict->$property = $value;
+    }
+
+    /**
+     * Return string trailer representation
+     *
+     * @return string
+     */
+    public function toString()
+    {
+        return "trailer\n" . $this->_dict->toString() . "\n";
+    }
+
+
+    /**
+     * Get length of source PDF
+     *
+     * @return string
+     */
+    abstract public function getPDFLength();
+
+    /**
+     * Get PDF String
+     *
+     * @return string
+     */
+    abstract public function getPDFString();
+
+    /**
+     * Get header of free objects list
+     * Returns object number of last free object
+     *
+     * @return integer
+     */
+    abstract public function getLastFreeObject();
+}