diff --git a/Modules/IGT/IO/mitkNavigationDataReaderXML.cpp b/Modules/IGT/IO/mitkNavigationDataReaderXML.cpp
index 25f97dcdfa..a7bdbbffdd 100644
--- a/Modules/IGT/IO/mitkNavigationDataReaderXML.cpp
+++ b/Modules/IGT/IO/mitkNavigationDataReaderXML.cpp
@@ -1,331 +1,355 @@
 /*===================================================================
 
 The Medical Imaging Interaction Toolkit (MITK)
 
 Copyright (c) German Cancer Research Center,
 Division of Medical and Biological Informatics.
 All rights reserved.
 
 This software is distributed WITHOUT ANY WARRANTY; without
 even the implied warranty of MERCHANTABILITY or FITNESS FOR
 A PARTICULAR PURPOSE.
 
 See LICENSE.txt or http://www.mitk.org for details.
 
 ===================================================================*/
 
 #include "mitkNavigationDataReaderXML.h"
 #include <itksys/SystemTools.hxx>
 #include <fstream>
 #include "tinyxml.h"
 
 //includes for exceptions
 #include "mitkIGTException.h"
 #include "mitkIGTIOException.h"
 
 mitk::NavigationDataReaderXML::NavigationDataReaderXML()
   : m_parentElement(0), m_currentNode(0)
 {
 }
 
 mitk::NavigationDataReaderXML::~NavigationDataReaderXML()
 {
 
 }
 
 mitk::NavigationDataSet::Pointer mitk::NavigationDataReaderXML::Read(std::string fileName)
 {
+  //save old locale
+  char * oldLocale;
+  oldLocale = setlocale( LC_ALL, 0 );
+
+  //define own locale
+  std::locale C("C");
+  setlocale( LC_ALL, "C" );
+
   m_FileName = fileName;
 
   TiXmlDocument document;
   if ( !document.LoadFile(fileName))
   {
     mitkThrowException(mitk::IGTIOException) << "File '"<<fileName<<"' could not be loaded.";
   }
 
   TiXmlElement* m_DataElem = document.FirstChildElement("Version");
   if(!m_DataElem)
   {
     // for backwards compatibility of version tag
     m_DataElem = document.FirstChildElement("Data");
     if(!m_DataElem)
     {
       mitkThrowException(mitk::IGTIOException) << "Data element not found.";
     }
 
   }
 
   if (m_DataElem->QueryIntAttribute("Ver", &m_FileVersion) != TIXML_SUCCESS)
   {
     if (m_DataElem->QueryIntAttribute("version", &m_FileVersion) != TIXML_SUCCESS)
     {
       mitkThrowException(mitk::IGTIOException) << "Version not specified in XML file.";
     }
   }
 
   if (m_FileVersion != 1)
   {
     mitkThrowException(mitk::IGTIOException) << "File format version "<<m_FileVersion<<" is not supported.";
   }
 
   m_parentElement = document.FirstChildElement("Data");
   if(!m_parentElement)
   {
     mitkThrowException(mitk::IGTIOException) << "Data element not found.";
   }
 
   m_parentElement->QueryIntAttribute("ToolCount", &m_NumberOfOutputs);
 
   mitk::NavigationDataSet::Pointer navigationDataSet = this->ReadNavigationDataSet();
 
+  //switch back to old locale
+  setlocale( LC_ALL, oldLocale );
+
   return navigationDataSet;
 }
 
 mitk::NavigationDataSet::Pointer mitk::NavigationDataReaderXML::Read(std::istream* stream)
 {
+  //save old locale
+  char * oldLocale;
+  oldLocale = setlocale( LC_ALL, 0 );
+
+  //define own locale
+  std::locale C("C");
+  setlocale( LC_ALL, "C" );
+
   // first get the file version
   m_FileVersion = this->GetFileVersion(stream);
 
   // check if we have a valid version: m_FileVersion has to be always bigger than 1 for playing
   if (m_FileVersion < 1)
   {
     StreamInvalid("Playing not possible. Invalid file version!");
     return 0;
   }
 
   m_NumberOfOutputs = this->GetNumberOfNavigationDatas(stream);
   if (m_NumberOfOutputs == 0) { return 0; }
 
-  return this->ReadNavigationDataSet();
+  mitk::NavigationDataSet::Pointer dataSet = this->ReadNavigationDataSet();
+
+  //switch back to old locale
+  setlocale( LC_ALL, oldLocale );
+
+  return dataSet;
 }
 
 mitk::NavigationDataSet::Pointer mitk::NavigationDataReaderXML::ReadNavigationDataSet()
 {
   mitk::NavigationDataSet::Pointer navigationDataSet = mitk::NavigationDataSet::New(m_NumberOfOutputs);
   mitk::NavigationData::Pointer curNavigationData;
 
   do
     {
       std::vector<mitk::NavigationData::Pointer> navDatas(m_NumberOfOutputs);
       for (unsigned int n = 0; n < m_NumberOfOutputs; ++n)
       {
         curNavigationData = this->ReadVersion1();
 
         if (curNavigationData.IsNull())
         {
           if (n != 0)
           {
             MITK_WARN("mitkNavigationDataReaderXML")
                 << "Different number of NavigationData objects for different tools. Ignoring last ones.";
           }
           break;
         }
         navDatas.at(n) = curNavigationData;
       }
 
       if (curNavigationData.IsNotNull())
       {
         navigationDataSet->AddNavigationDatas(navDatas);
       }
     }
     while (curNavigationData.IsNotNull());
 
     return navigationDataSet;
 }
 
 mitk::NavigationData::Pointer mitk::NavigationDataReaderXML::ReadVersion1()
 {
   if ( !m_parentElement )
   {
     mitkThrowException(mitk::IGTIOException)
         << "Reading XML is not possible. Parent element is not set.";
   }
 
   TiXmlElement* elem;
   m_currentNode = m_parentElement->IterateChildren(m_currentNode);
 
   bool delElem;
 
   if(m_currentNode)
   {
     elem = m_currentNode->ToElement();
     if(elem==NULL)
     {
       mitkThrowException(mitk::IGTException) << "Cannot find element: Is this file damaged?";
     }
     delElem = false;
   }
 
   else
   {
     elem = new TiXmlElement("");
     delElem = true;
   }
 
 
   mitk::NavigationData::Pointer nd = this->ReadNavigationData(elem);
 
   if(delElem) { delete elem; }
 
   return nd;
 }
 
 mitk::NavigationData::Pointer mitk::NavigationDataReaderXML::ReadNavigationData(TiXmlElement* elem)
 {
   if (elem == NULL) {mitkThrow() << "Error: Element is NULL!";}
 
   mitk::NavigationData::Pointer nd = mitk::NavigationData::New();
 
   mitk::NavigationData::PositionType position;
   mitk::NavigationData::OrientationType orientation(0.0,0.0,0.0,0.0);
   mitk::NavigationData::TimeStampType timestamp = -1;
   mitk::NavigationData::CovarianceMatrixType matrix;
 
   bool hasPosition = true;
   bool hasOrientation = true;
   bool dataValid = false;
 
   position.Fill(0.0);
   matrix.SetIdentity();
 
   elem->QueryDoubleAttribute("Time",&timestamp);
   if (timestamp == -1)
   {
     return NULL;  //the calling method should check the return value if it is valid/not NULL
   }
 
   elem->QueryDoubleAttribute("X", &position[0]);
   elem->QueryDoubleAttribute("Y", &position[1]);
   elem->QueryDoubleAttribute("Z", &position[2]);
 
   elem->QueryDoubleAttribute("QX", &orientation[0]);
   elem->QueryDoubleAttribute("QY", &orientation[1]);
   elem->QueryDoubleAttribute("QZ", &orientation[2]);
   elem->QueryDoubleAttribute("QR", &orientation[3]);
 
   elem->QueryDoubleAttribute("C00", &matrix[0][0]);
   elem->QueryDoubleAttribute("C01", &matrix[0][1]);
   elem->QueryDoubleAttribute("C02", &matrix[0][2]);
   elem->QueryDoubleAttribute("C03", &matrix[0][3]);
   elem->QueryDoubleAttribute("C04", &matrix[0][4]);
   elem->QueryDoubleAttribute("C05", &matrix[0][5]);
   elem->QueryDoubleAttribute("C10", &matrix[1][0]);
   elem->QueryDoubleAttribute("C11", &matrix[1][1]);
   elem->QueryDoubleAttribute("C12", &matrix[1][2]);
   elem->QueryDoubleAttribute("C13", &matrix[1][3]);
   elem->QueryDoubleAttribute("C14", &matrix[1][4]);
   elem->QueryDoubleAttribute("C15", &matrix[1][5]);
 
   int tmpval = 0;
   elem->QueryIntAttribute("Valid", &tmpval);
   if (tmpval == 0)
     dataValid = false;
   else
     dataValid = true;
 
   tmpval = 0;
   elem->QueryIntAttribute("hO", &tmpval);
   if (tmpval == 0)
     hasOrientation = false;
   else
     hasOrientation = true;
 
   tmpval = 0;
   elem->QueryIntAttribute("hP", &tmpval);
   if (tmpval == 0)
     hasPosition = false;
   else
     hasPosition = true;
 
   nd->SetIGTTimeStamp(timestamp);
   nd->SetPosition(position);
   nd->SetOrientation(orientation);
   nd->SetCovErrorMatrix(matrix);
   nd->SetDataValid(dataValid);
   nd->SetHasOrientation(hasOrientation);
   nd->SetHasPosition(hasPosition);
 
 
   return nd;
 }
 
 // -- deprecated | begin
 unsigned int mitk::NavigationDataReaderXML::GetFileVersion(std::istream* stream)
 {
   if (stream==NULL)
   {
     MITK_ERROR << "No input stream set!";
     mitkThrowException(mitk::IGTIOException)<<"No input stream set!";
   }
   if (!stream->good())
   {
     MITK_ERROR << "Stream is not good!";
     mitkThrowException(mitk::IGTIOException)<<"Stream is not good!";
   }
   int version = 1;
 
   TiXmlDeclaration* dec = new TiXmlDeclaration();
   *stream >> *dec;
   if(strcmp(dec->Version(),"") == 0)
   {
     MITK_ERROR << "The input stream seems to have XML incompatible format";
     mitkThrowException(mitk::IGTIOException) << "The input stream seems to have XML incompatible format";
   }
 
   m_parentElement = new TiXmlElement("");
   *stream >> *m_parentElement; //2nd line this is the file version
 
   std::string tempValue = m_parentElement->Value();
   if(tempValue != "Version")
   {
       if(tempValue == "Data"){
           m_parentElement->QueryIntAttribute("version",&version);
       }
   }
   else
   {
     m_parentElement->QueryIntAttribute("Ver",&version);
   }
 
   if (version > 0) { return version; }
   else { return 0; }
 }
 
 unsigned int mitk::NavigationDataReaderXML::GetNumberOfNavigationDatas(std::istream* stream)
 {
   if (stream == NULL)
   {
     MITK_ERROR << "No input stream set!";
     mitkThrowException(mitk::IGTException)<<"No input stream set!";
   }
   if (!stream->good())
   {
     MITK_ERROR << "Stream not good!";
     mitkThrowException(mitk::IGTException)<<"Stream not good!";
   }
 
   //If something has changed in a future version of the XML definition e.g. navigationcount or addional parameters
   //catch this here with a select case block (see GenerateData() method)
 
   int numberOfTools = 0;
 
   std::string tempValue = m_parentElement->Value();
   if(tempValue == "Version"){
     *stream >> *m_parentElement;
   }
   m_parentElement->QueryIntAttribute("ToolCount",&numberOfTools);
 
   if (numberOfTools > 0) { return numberOfTools; }
 
   return 0;
 }
 
 void mitk::NavigationDataReaderXML::StreamInvalid(std::string message)
 {
   m_StreamEnd = true;
   m_ErrorMessage = message;
   m_StreamValid = false;
   mitkThrowException(mitk::IGTIOException) << "Invalid stream!";
 }
 // -- deprecated | end
 
diff --git a/Modules/IGT/IO/mitkNavigationDataSetWriterCSV.cpp b/Modules/IGT/IO/mitkNavigationDataSetWriterCSV.cpp
index 18c682953c..dd4ff8a322 100644
--- a/Modules/IGT/IO/mitkNavigationDataSetWriterCSV.cpp
+++ b/Modules/IGT/IO/mitkNavigationDataSetWriterCSV.cpp
@@ -1,74 +1,85 @@
 /*===================================================================
 
 The Medical Imaging Interaction Toolkit (MITK)
 
 Copyright (c) German Cancer Research Center,
 Division of Medical and Biological Informatics.
 All rights reserved.
 
 This software is distributed WITHOUT ANY WARRANTY; without
 even the implied warranty of MERCHANTABILITY or FITNESS FOR
 A PARTICULAR PURPOSE.
 
 See LICENSE.txt or http://www.mitk.org for details.
 
 ===================================================================*/
 
 #include "mitkNavigationDataSetWriterCSV.h"
 #include <fstream>
 
 void mitk::NavigationDataSetWriterCSV::Write (std::string path, mitk::NavigationDataSet::Pointer data)
 {
   MITK_INFO << "Writing navigation data set to file: " << path;
   std::ofstream stream;
   stream.open (path.c_str(), std::ios_base::trunc);
 
   // Pass to Stream Handler
   Write(&stream, data);
   stream.close();
 }
 
 void mitk::NavigationDataSetWriterCSV::Write (std::ostream* stream, mitk::NavigationDataSet::Pointer data)
 {
+  //save old locale
+  char * oldLocale;
+  oldLocale = setlocale( LC_ALL, 0 );
+
+  //define own locale
+  std::locale C("C");
+  setlocale( LC_ALL, "C" );
+
   //write header
   int numberOfTools = data->GetNumberOfTools();
   for (unsigned int index = 0; index < numberOfTools; index++){ *stream << "TimeStamp_Tool" << index <<
                                                                            ";Valid_Tool" << index <<
                                                                            ";X_Tool" << index <<
                                                                            ";Y_Tool" << index <<
                                                                            ";Z_Tool" << index <<
                                                                            ";QX_Tool" << index <<
                                                                            ";QY_Tool" << index <<
                                                                            ";QZ_Tool" << index <<
                                                                            ";QR_Tool" << index << ";";}
   *stream << "\n";
 
   stream->precision(15); // rounding precision because we don't want to loose data.
 
   //write data
   MITK_INFO << "Number of timesteps: " << data->Size();
   for (int i=0; i<data->Size(); i++)
   {
     std::vector< mitk::NavigationData::Pointer > NavigationDatasOfCurrentStep = data->GetTimeStep(i);
     for (int toolIndex = 0; toolIndex < numberOfTools; toolIndex++)
     {
       mitk::NavigationData::Pointer nd = NavigationDatasOfCurrentStep.at(toolIndex);
       *stream          << nd->GetTimeStamp() << ";"
                        << nd->IsDataValid() << ";"
                        << nd->GetPosition()[0] << ";"
                        << nd->GetPosition()[1] << ";"
                        << nd->GetPosition()[2] << ";"
                        << nd->GetOrientation()[0] << ";"
                        << nd->GetOrientation()[1] << ";"
                        << nd->GetOrientation()[2] << ";"
                        << nd->GetOrientation()[3] << ";";
     }
     *stream << "\n";
   }
+
+  //switch back to old locale
+  setlocale( LC_ALL, oldLocale );
 }
 
 mitk::NavigationDataSetWriterCSV::NavigationDataSetWriterCSV()
 {}
 
 mitk::NavigationDataSetWriterCSV::~NavigationDataSetWriterCSV()
 {}
diff --git a/Modules/IGT/IO/mitkNavigationDataSetWriterXML.cpp b/Modules/IGT/IO/mitkNavigationDataSetWriterXML.cpp
index 9ce7eee434..eb6d8d7c9a 100644
--- a/Modules/IGT/IO/mitkNavigationDataSetWriterXML.cpp
+++ b/Modules/IGT/IO/mitkNavigationDataSetWriterXML.cpp
@@ -1,130 +1,137 @@
 /*===================================================================
 
 The Medical Imaging Interaction Toolkit (MITK)
 
 Copyright (c) German Cancer Research Center,
 Division of Medical and Biological Informatics.
 All rights reserved.
 
 This software is distributed WITHOUT ANY WARRANTY; without
 even the implied warranty of MERCHANTABILITY or FITNESS FOR
 A PARTICULAR PURPOSE.
 
 See LICENSE.txt or http://www.mitk.org for details.
 
 ===================================================================*/
 
 // MITK
 #include "mitkNavigationDataSetWriterXML.h"
 
 // Third Party
 #include <tinyxml.h>
 #include <itksys/SystemTools.hxx>
 #include <fstream>
 #include <iostream>
 
 mitk::NavigationDataSetWriterXML::NavigationDataSetWriterXML()
 {
 }
 
 mitk::NavigationDataSetWriterXML::~NavigationDataSetWriterXML()
 {
 }
 
 void mitk::NavigationDataSetWriterXML::Write (std::string path, mitk::NavigationDataSet::Pointer data)
 {
   std::ofstream stream;
   stream.open (path.c_str(), std::ios_base::trunc);
 
   // Pass to Stream Handler
   Write(&stream, data);
   stream.close();
 }
 
 void mitk::NavigationDataSetWriterXML::Write (std::ostream* stream, mitk::NavigationDataSet::Pointer data)
 {
+  //save old locale
+  char * oldLocale;
+  oldLocale = setlocale( LC_ALL, 0 );
+
   StreamHeader(stream, data);
   StreamData(stream, data);
   StreamFooter(stream);
 
   // Cleanup
 
   stream->flush();
+
+  //switch back to old locale
+  setlocale( LC_ALL, oldLocale );
 }
 
 void mitk::NavigationDataSetWriterXML::StreamHeader (std::ostream* stream, mitk::NavigationDataSet::Pointer data)
 {
   stream->precision(10);
 
   //TODO store date and GMT time
   //checking if the stream is good
   if (stream->good())
   {
     *stream << "<?xml version=\"1.0\" encoding=\"UTF-8\" standalone=\"yes\"?>" << std::endl;
     /**m_Stream << "<Version Ver=\"1\" />" << std::endl;*/
     // should be a generic version, meaning a member variable, which has the actual version
     *stream << "    " << "<Data ToolCount=\"" << data->GetNumberOfTools() << "\" version=\"1.0\">" << std::endl;
   }
 }
 
 void mitk::NavigationDataSetWriterXML::StreamData (std::ostream* stream, mitk::NavigationDataSet::Pointer data)
 {
   // For each time step in the Dataset
   for (mitk::NavigationDataSet::NavigationDataSetIterator it = data->Begin(); it != data->End(); it++)
   {
     for (int toolIndex = 0; toolIndex < it->size(); toolIndex++)
     {
       mitk::NavigationData::Pointer nd = it->at(toolIndex);
       TiXmlElement* elem = new TiXmlElement("ND");
 
       elem->SetDoubleAttribute("Time", nd->GetIGTTimeStamp());
       // elem->SetAttribute("SystemTime", sysTimeStr); // tag for system time
       elem->SetDoubleAttribute("Tool", toolIndex);
       elem->SetDoubleAttribute("X", nd->GetPosition()[0]);
       elem->SetDoubleAttribute("Y", nd->GetPosition()[1]);
       elem->SetDoubleAttribute("Z", nd->GetPosition()[2]);
 
       elem->SetDoubleAttribute("QX", nd->GetOrientation()[0]);
       elem->SetDoubleAttribute("QY", nd->GetOrientation()[1]);
       elem->SetDoubleAttribute("QZ", nd->GetOrientation()[2]);
       elem->SetDoubleAttribute("QR", nd->GetOrientation()[3]);
 
       elem->SetDoubleAttribute("C00", nd->GetCovErrorMatrix()[0][0]);
       elem->SetDoubleAttribute("C01", nd->GetCovErrorMatrix()[0][1]);
       elem->SetDoubleAttribute("C02", nd->GetCovErrorMatrix()[0][2]);
       elem->SetDoubleAttribute("C03", nd->GetCovErrorMatrix()[0][3]);
       elem->SetDoubleAttribute("C04", nd->GetCovErrorMatrix()[0][4]);
       elem->SetDoubleAttribute("C05", nd->GetCovErrorMatrix()[0][5]);
       elem->SetDoubleAttribute("C10", nd->GetCovErrorMatrix()[1][0]);
       elem->SetDoubleAttribute("C11", nd->GetCovErrorMatrix()[1][1]);
       elem->SetDoubleAttribute("C12", nd->GetCovErrorMatrix()[1][2]);
       elem->SetDoubleAttribute("C13", nd->GetCovErrorMatrix()[1][3]);
       elem->SetDoubleAttribute("C14", nd->GetCovErrorMatrix()[1][4]);
       elem->SetDoubleAttribute("C15", nd->GetCovErrorMatrix()[1][5]);
 
       if (nd->IsDataValid())
         elem->SetAttribute("Valid",1);
       else
         elem->SetAttribute("Valid",0);
 
       if (nd->GetHasOrientation())
         elem->SetAttribute("hO",1);
       else
         elem->SetAttribute("hO",0);
 
       if (nd->GetHasPosition())
         elem->SetAttribute("hP",1);
       else
         elem->SetAttribute("hP",0);
 
       *stream << "        " << *elem << std::endl;
 
       delete elem;
     }
   }
 }
 
 void mitk::NavigationDataSetWriterXML::StreamFooter (std::ostream* stream)
 {
   *stream << "</Data>" << std::endl;
 }