diff --git a/lib/Doctrine/Query/Filter.php b/lib/Doctrine/Query/Filter.php
new file mode 100644
index 000000000..95d2e884c
--- /dev/null
+++ b/lib/Doctrine/Query/Filter.php
@@ -0,0 +1,61 @@
+<?php
+/*
+ *  $Id$
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ *
+ * This software consists of voluntary contributions made by many individuals
+ * and is licensed under the LGPL. For more information, see
+ * <http://www.phpdoctrine.com>.
+ */
+
+/**
+ * Doctrine_Query_Filter
+ *
+ * @package     Doctrine
+ * @license     http://www.opensource.org/licenses/lgpl-license.php LGPL
+ * @category    Object Relational Mapping
+ * @link        www.phpdoctrine.com
+ * @since       1.0
+ * @version     $Revision$
+ * @author      Konsta Vesterinen <kvesteri@cc.hut.fi>
+ */
+class Doctrine_Query_Filter implements Doctrine_Query_Filter_Interface
+{
+    /**
+     * preQuery
+     *
+     * Method for listening the preQuery method of Doctrine_Query and
+     * hooking into the query building procedure, doing any custom / specialized
+     * query building procedures that are neccessary.
+     *
+     * @return void
+     */
+    public function preQuery(Doctrine_Query $query)
+    {
+    
+    }
+    /**
+     * postQuery
+     *
+     * Method for listening the postQuery method of Doctrine_Query and
+     * to hook into the query building procedure, doing any custom / specialized
+     * post query procedures (for example logging) that are neccessary.
+     *
+     * @return void
+     */
+    public function postQuery(Doctrine_Query $query)
+    {
+    
+    }
+}
diff --git a/lib/Doctrine/Query/Filter/Chain.php b/lib/Doctrine/Query/Filter/Chain.php
new file mode 100644
index 000000000..f5a0e532b
--- /dev/null
+++ b/lib/Doctrine/Query/Filter/Chain.php
@@ -0,0 +1,104 @@
+<?php
+/*
+ *  $Id$
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ *
+ * This software consists of voluntary contributions made by many individuals
+ * and is licensed under the LGPL. For more information, see
+ * <http://www.phpdoctrine.com>.
+ */
+
+/**
+ * Doctrine_Query_Filter_Chain
+ *
+ * @package     Doctrine
+ * @license     http://www.opensource.org/licenses/lgpl-license.php LGPL
+ * @category    Object Relational Mapping
+ * @link        www.phpdoctrine.com
+ * @since       1.0
+ * @version     $Revision$
+ * @author      Konsta Vesterinen <kvesteri@cc.hut.fi>
+ */
+class Doctrine_Query_Filter_Chain
+{
+    /**
+     * @var array $_filters         an array of Doctrine_Query_Filter objects
+     */
+    protected $_filters = array();
+    /**
+     * add
+     *
+     * @param Doctrine_Query_Filter $filter
+     * @return void
+     */
+    public function add(Doctrine_Query_Filter $filter)
+    {
+        $this->_filters[] = $filter;
+    }
+    /**
+     * returns a Doctrine_Query_Filter on success
+     * and null on failure
+     *
+     * @param mixed $key
+     * @return mixed
+     */
+    public function get($key)
+    {
+        if ( ! isset($this->_filters[$key])) {
+            throw new Doctrine_Query_Exception('Unknown filter ' . $key);
+        }
+        return $this->_filters[$key];
+    }
+    /**
+     * set
+     *
+     * @param mixed $key
+     * @param Doctrine_Query_Filter $listener
+     * @return void
+     */
+    public function set($key, Doctrine_Query_Filter $listener)
+    {
+        $this->_filters[$key] = $listener;
+    }
+    /**
+     * preQuery
+     *
+     * Method for listening the preQuery method of Doctrine_Query and
+     * hooking into the query building procedure, doing any custom / specialized
+     * query building procedures that are neccessary.
+     *
+     * @return void
+     */
+    public function preQuery(Doctrine_Query $query)
+    {
+        foreach ($this->_filters as $filter) {
+            $filter->preQuery($query);
+        }
+    }
+    /**
+     * postQuery
+     *
+     * Method for listening the postQuery method of Doctrine_Query and
+     * to hook into the query building procedure, doing any custom / specialized
+     * post query procedures (for example logging) that are neccessary.
+     *
+     * @return void
+     */
+    public function postQuery(Doctrine_Query $query)
+    {
+        foreach ($this->_filters as $filter) {
+            $filter->postQuery($query);
+        }
+    }
+}
diff --git a/lib/Doctrine/Query/Filter/Interface.php b/lib/Doctrine/Query/Filter/Interface.php
new file mode 100644
index 000000000..4ad8e22ec
--- /dev/null
+++ b/lib/Doctrine/Query/Filter/Interface.php
@@ -0,0 +1,57 @@
+<?php
+/*
+ *  $Id$
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ *
+ * This software consists of voluntary contributions made by many individuals
+ * and is licensed under the LGPL. For more information, see
+ * <http://www.phpdoctrine.com>.
+ */
+
+/**
+ * Doctrine_Query_Filter_Interface
+ *
+ * @package     Doctrine
+ * @license     http://www.opensource.org/licenses/lgpl-license.php LGPL
+ * @category    Object Relational Mapping
+ * @link        www.phpdoctrine.com
+ * @since       1.0
+ * @version     $Revision$
+ * @author      Konsta Vesterinen <kvesteri@cc.hut.fi>
+ */
+interface Doctrine_Query_Filter_Interface
+{
+
+    /**
+     * preQuery
+     *
+     * Method for listening the preQuery method of Doctrine_Query and
+     * hooking into the query building procedure, doing any custom / specialized
+     * query building procedures that are neccessary.
+     *
+     * @return void
+     */
+    public function preQuery(Doctrine_Query $query);
+
+    /**
+     * postQuery
+     *
+     * Method for listening the postQuery method of Doctrine_Query and
+     * to hook into the query building procedure, doing any custom / specialized
+     * post query procedures (for example logging) that are neccessary.
+     *
+     * @return void
+     */
+    public function postQuery(Doctrine_Query $query);
+}