diff --git a/akonadi/preprocessorbase.h b/akonadi/preprocessorbase.h
index 77227b040..cda0daf4c 100644
--- a/akonadi/preprocessorbase.h
+++ b/akonadi/preprocessorbase.h
@@ -1,169 +1,167 @@
 /******************************************************************************
  *
  *  Copyright (c) 2009 Szymon Stefanek <s.stefanek at gmail dot com>
  *
  *  This library is free software; you can redistribute it and/or modify it
  *  under the terms of the GNU Library General Public License as published by
  *  the Free Software Foundation; either version 2 of the License, or (at your
  *  option) any later version.
  *
  *  This library is distributed in the hope that it will be useful, but WITHOUT
  *  ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  *  FITNESS FOR A PARTICULAR PURPOSE.  See the GNU Library General Public
  *  License for more details.
  *
  *  You should have received a copy of the GNU Library General Public License
  *  along with this library; see the file COPYING.LIB.  If not, write to the
  *  Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston,
  *  MA, 02110-1301, USA.
  *
  *****************************************************************************/
 
 #ifndef AKONADI_PREPROCESSORBASE_H
 #define AKONADI_PREPROCESSORBASE_H
 
 #include "akonadi_export.h"
 
 #include <akonadi/agentbase.h>
 
 class PreprocessorAdaptor;
 
 namespace Akonadi
 {
 
 class Item;
 class PreprocessorBasePrivate;
 
 /**
  * @short The base class for all Akonadi preprocessor agents.
  *
  * This class should be used as a base class by all preprocessor agents
  * since it encapsulates large parts of the protocol between
  * preprocessor agent, agent manager and the Akonadi storage.
  *
  * Preprocessor agents are special agents that are informed about newly
  * added items before any other agents. This allows them to do filtering
  * on the items or any other task that shall be done before the new item
  * is visible in the Akonadi storage system.
  *
  * The method all the preprocessors must implement is processItem().
  *
  * @author Szymon Stefanek <s.stefanek@gmail.com>
  * @since 4.4
  */
 class AKONADI_EXPORT PreprocessorBase : public AgentBase
 {
-  friend class PreprocessorAdaptor;
-
   Q_OBJECT
 
   public:
     /**
      * Describes the possible return values of the processItem() method.
      */
     enum ProcessingResult
     {
       /**
        * Processing completed succesfully for this item.
        * The Akonadi server will push in a new item when it's available.
        */
       ProcessingCompleted,
 
       /**
        * Processing was delayed to a later stage.
        * This must be returned when implementing asynchronous preprocessing.
        *
        * If this value is returned, terminateProcessing() has to be called
        * when processing is done.
        */
       ProcessingDelayed,
 
       /**
        * Processing for this item failed (and the failure is unrecoverable).
        * The Akonadi server will push in a new item when it's available,
        * after possibly logging the failure.
        */
       ProcessingFailed,
 
       /**
        * Processing for this item was refused. This is very
        * similar to ProcessingFailed above but additionally remarks
        * that the item that the Akonadi server pushed in wasn't
        * meant for this Preprocessor.
        * The Akonadi server will push in a new item when it's available,
        * after possibly logging the failure and maybe taking some additional action.
        */
       ProcessingRefused
     };
 
     /**
      * This method has to be implement by every preprocessor subclass.
      *
      * Returns ProcessingCompleted on success, ProcessingDelayed
      * if processing is implemented asynchronously and
      * ProcessingRefused or ProcessingFailed if the processing
      * didn't complete.
      */
     virtual ProcessingResult processItem( const Item &item ) = 0;
 
     /**
      * This method must be called if processing is implemented asynchronously.
      *
      * Valid values for @p result are ProcessingCompleted,
      * PocessingRefused and ProcessingFailed. Passing any
      * other value will lead to a runtime assertion.
      */
     void terminateProcessing( ProcessingResult result );
 
   Q_SIGNALS:
     /**
      * This signal is emitted to report item processing termination
      * to the Akonadi server.
      *
      * @note This signal is only for internal use.
      */
     void itemProcessed( qlonglong id );
 
   protected:
     /**
      * Creates a new preprocessor base agent.
      *
      * @param id The instance id of the preprocessor base agent.
      */
     PreprocessorBase( const QString &id );
 
     /**
      * Destroys the preprocessor base agent.
      */
     virtual ~PreprocessorBase();
 
     /**
      * This dbus method is called by the Akonadi server
      * in order to trigger the processing of an item.
      *
      * @note Do not call it manually!
      */
     void beginProcessItem( qlonglong itemId );
 
   private:
     // dbus Preprocessor interface
     friend class ::PreprocessorAdaptor;
 
     Q_DECLARE_PRIVATE( PreprocessorBase )
 
 }; // class PreprocessorBase
 
 } // namespace Akonadi
 
 #ifndef AKONADI_PREPROCESSOR_MAIN
 /**
  * Convenience Macro for the most common main() function for Akonadi preprocessors.
  */
 #define AKONADI_PREPROCESSOR_MAIN( preProcessorClass )                       \
   int main( int argc, char **argv )                                          \
   {                                                                          \
     return Akonadi::PreprocessorBase::init<preProcessorClass>( argc, argv ); \
   }
 #endif //!AKONADI_RESOURCE_MAIN
 
 #endif //!_PREPROCESSORBASE_H_