diff --git a/Modules/PlanarFigure/DataManagement/mitkPlanarRectangle.cpp b/Modules/PlanarFigure/DataManagement/mitkPlanarRectangle.cpp
index 5916f07b23..6b6b7e8611 100644
--- a/Modules/PlanarFigure/DataManagement/mitkPlanarRectangle.cpp
+++ b/Modules/PlanarFigure/DataManagement/mitkPlanarRectangle.cpp
@@ -1,150 +1,150 @@
 /*===================================================================
 
 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 "mitkProperties.h"
 
 #include "mitkPlanarRectangle.h"
 #include "mitkGeometry2D.h"
 
 
 mitk::PlanarRectangle::PlanarRectangle()
 : FEATURE_ID_CIRCUMFERENCE( this->AddFeature( "Circumference", "mm" ) ),
   FEATURE_ID_AREA( this->AddFeature( "Area", "mm2" ) )
 {
   // Rectangle has four control points
   this->ResetNumberOfControlPoints( 4 );
   this->SetProperty( "closed", mitk::BoolProperty::New(true) );
   this->SetNumberOfPolyLines( 1 );
 }
 
 
 mitk::PlanarRectangle::~PlanarRectangle()
 {
 }
 
 
 bool mitk::PlanarRectangle::SetControlPoint( unsigned int index, const Point2D &point, bool createIfDoesNotExist )
 {
   // heres the deal with the rectangle:
   // when a point is moved all corresponding corner points are moved with him
   // e.g. if the lower right point (index=3) is moved the upper right point (index=1)
   // is moved in the same x direction
   // and the lower left point (index=2) is moved in the same y direction
   // the upper left point (index=0) is left untouched
   bool set = PlanarFigure::SetControlPoint( index, point, createIfDoesNotExist );
 
   if(set)
   {
     // can be made better ...
     unsigned int horizontalCorrespondingPointIndex = 1;
     unsigned int verticalCorrespondingPointIndex = 3;
     if(index == 1)
     {
       horizontalCorrespondingPointIndex = 0;
       verticalCorrespondingPointIndex = 2;
     }
     else if(index == 2)
     {
       horizontalCorrespondingPointIndex = 3;
       verticalCorrespondingPointIndex = 1;
     }
     else if(index == 3)
     {
       horizontalCorrespondingPointIndex = 2;
       verticalCorrespondingPointIndex = 0;
     }
 
     Point2D verticalCorrespondingPoint = GetControlPoint( verticalCorrespondingPointIndex );
     verticalCorrespondingPoint[0] = point[0];
     PlanarFigure::SetControlPoint( verticalCorrespondingPointIndex, verticalCorrespondingPoint );
 
     Point2D horizontalCorrespondingPoint = GetControlPoint( horizontalCorrespondingPointIndex );
     horizontalCorrespondingPoint[1] = point[1];
     PlanarFigure::SetControlPoint( horizontalCorrespondingPointIndex, horizontalCorrespondingPoint );
   }
 
   return set;
 }
 
 void mitk::PlanarRectangle::PlaceFigure( const mitk::Point2D &point )
 {
   PlanarFigure::PlaceFigure( point );
   m_SelectedControlPoint = 3;
 }
 
 void mitk::PlanarRectangle::GeneratePolyLine()
 {
   // TODO: start polygon at specified initalize point...
 
   ClearPolyLines();
 
   for ( unsigned int i = 0; i < this->GetNumberOfControlPoints(); ++i )
   {
     AppendPointToPolyLine( 0, PolyLineElement( GetControlPoint(i), i ) );
   }
 }
 
 void mitk::PlanarRectangle::GenerateHelperPolyLine(double /*mmPerDisplayUnit*/, unsigned int /*displayHeight*/)
 {
   // A polygon does not require helper objects
 }
 
 void mitk::PlanarRectangle::EvaluateFeaturesInternal()
 {
   // Calculate circumference
   double circumference = 0.0;
   unsigned int i;
   for ( i = 0; i < this->GetNumberOfControlPoints(); ++i )
   {
     circumference += this->GetWorldControlPoint( i ).EuclideanDistanceTo(
       this->GetWorldControlPoint( (i + 1) % this->GetNumberOfControlPoints() ) );
   }
 
   this->SetQuantity( FEATURE_ID_CIRCUMFERENCE, circumference );
 
 
   // Calculate rectangle area (well, done a bit clumsy...)
   double area = 0.0;
   if ( this->GetGeometry2D() != NULL )
   {
     for ( i = 0; i < this->GetNumberOfControlPoints(); ++i )
     {
       Point2D p0 = this->GetControlPoint( i );
       Point2D p1 = this->GetControlPoint( (i + 1) % this->GetNumberOfControlPoints() );
 
       area += p0[0] * p1[1] - p1[0] * p0[1];
     }
     area /= 2.0;
   }
 
-  this->SetQuantity( FEATURE_ID_AREA, abs(area) );
+  this->SetQuantity( FEATURE_ID_AREA, fabs(area) );
 
 }
 
 
 void mitk::PlanarRectangle::PrintSelf( std::ostream& os, itk::Indent indent) const
 {
   Superclass::PrintSelf( os, indent );
 
   os << indent << "Number of control points: " << this->GetNumberOfControlPoints() << std::endl;
 
   os << indent << "Control points:" << std::endl;
 
   for ( unsigned int i = 0; i < this->GetNumberOfControlPoints(); ++i )
   {
     os << indent << indent << i << ": " <<GetControlPoint( i ) << std::endl;
   }
 }