diff --git a/Modules/IGT/IGTTrackingDevices/mitkClaronInterface.h b/Modules/IGT/IGTTrackingDevices/mitkClaronInterface.h
index 5f2e178f14..ef73ca02c8 100644
--- a/Modules/IGT/IGTTrackingDevices/mitkClaronInterface.h
+++ b/Modules/IGT/IGTTrackingDevices/mitkClaronInterface.h
@@ -1,145 +1,149 @@
 /*=========================================================================
 
 Program:   Medical Imaging & Interaction Toolkit
 Language:  C++
 Date:      $Date$
 Version:   $Revision$
 
 Copyright (c) German Cancer Research Center, Division of Medical and
 Biological Informatics. All rights reserved.
 See MITKCopyright.txt or http://www.mitk.org/copyright.html for details.
 
 This software is distributed WITHOUT ANY WARRANTY; without even
 the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR
 PURPOSE.  See the above copyright notices for more information.
 
 =========================================================================*/
 
 #ifndef MITKCLARONINTERFACE_H_HEADER_INCLUDED_
 #define MITKCLARONINTERFACE_H_HEADER_INCLUDED_
 #define MTC(func) {int r = func; if (r!=mtOK) printf("MTC error: %s\n",MTLastErrorString()); };
 
 #include <vector>
 #include <string>
 
 #include <MitkIGTExports.h>
 #include "mitkCommon.h"
 
 #include <itkObject.h>
 #include <itkObjectFactory.h>
 
-typedef int mtHandle;
+#ifdef _WIN64  //Defined for applications for Win64.
+typedef long mtHandle; 
+#else 
+typedef int mtHandle; 
+#endif
 
 namespace mitk
 {
   typedef int claronToolHandle;
 
   /** Documentation:
   *   \brief An object of this class represents the interface to the MicronTracker. The methods of this class
   *          are calling the c-functions which are provided by the MTC-library. If the MicronTracker is not in
   *          use, which means the CMake-variable "MITK_USE_MICRON_TRACKER" is set to OFF, this class is replaced
   *          by a stub class called "ClaronInterfaceStub". 
   *   \ingroup IGT
   */
   class MitkIGT_EXPORT ClaronInterface : public itk::Object
   {
   public:
     
     mitkClassMacro(ClaronInterface,itk::Object);
     itkNewMacro(Self);
     /**
     * \brief Initialization of claroninterface.
     * \param calibrationDir   The directory where the device can find the camera calibration file.
     * \param toolFilesDir     The directory for the tool files.
     */
     void Initialize(std::string calibrationDir, std::string toolFilesDir);
 
     /**
     * \brief Opens the connection to the device and makes it ready to track tools. 
     * \return Returns true if there is a connection to the device and the device is ready to track tools, false if not.
     */
     bool StartTracking();
 
     /**
     * \brief Clears all resources. After this method have been called the system isn't ready to track any longer.
     * \return Returns true if the operation was succesful, false if not.
     */
     bool StopTracking();
 
     /**
     * \return Returns all tools which have been detected at the last frame grab.
     */
     std::vector<claronToolHandle> GetAllActiveTools();
 
     /**
     * \return Returns the position of the tooltip. If no tooltip is defined the Method returns the position of the tool.
     */
     std::vector<double> GetTipPosition(claronToolHandle c);
 
     /**
     * \return Returns the quarternions of the tooltip. If no tooltip is defined the Method returns the quarternions of the tool.
     */
     std::vector<double> GetTipQuaternions(claronToolHandle c);
 
     /**
     * \return Returns the position of the tool
     */
     std::vector<double> GetPosition(claronToolHandle c);
 
     /**
     * \return Returns the quaternion of the tool.
     */
     std::vector<double> GetQuaternions(claronToolHandle c);
 
     /**
     * \return Returns the name of the tool. This name is given by the calibration file.
     * \param c The handle of the tool, which name should be given back.
     */
     const char* GetName(claronToolHandle c);
 
     /**
     * \brief Grabs a frame from the camera.
     */
     void GrabFrame();
 
     /**
     * \return Returns wether the tracking device is tracking or not.
     */
     bool IsTracking();
     
     /**
     * \return   Returns wether the MicronTracker is installed (means wether the C-Make-Variable "MITK_USE_MICRON_TRACKER" is set ON),
     *           so returns true in this case. This is because the class mitkClaronInterfaceStub, in which the same Method returns false 
     *            is used otherways.
     */
     bool IsMicronTrackerInstalled();
 
   protected:
     /**
     * \brief standard constructor
     */
     ClaronInterface();
     /**
     * \brief standard destructor
     */
     ~ClaronInterface();
 
 
     /** \brief Variable is true if the device is tracking at the moment, false if not.*/
     bool isTracking;
 
     /** \brief Variable which holds the directory which should contain the file BumbleBee_6400420.calib. This directory is needed by the MTC library.*/
     char calibrationDir[512];
     /** \brief Variable which holds a directory with some tool files in it. All this tools are trackable when the path is given to the MTC library.*/
     char markerDir[512];
 
     //Some handles to communicate with the MTC library.
     mtHandle IdentifiedMarkers;
     mtHandle PoseXf;
     mtHandle CurrCamera;
     mtHandle IdentifyingCamera;
     //------------------------------------------------
 
   };
 }//mitk
 #endif