[vtkusers] problems with vtkImagePlaneWidget

[N.E Mackenzie-Mackay]

Hi,

	I am having a problem with the vtkImagePlaneWidget.  When I include  
vtkImagePlaneWidget.h I get a bunch of linking errors.  Even when I  
haven't written anything in my code that references the widget.

If anyone could please help that you be great,
Neilson

Medical1.obj : error LNK2001: unresolved external symbol  
"__declspec(dllimport) public: static int __cdecl  
vtkPolyDataSourceWidget::IsTypeOf(char const *)"  
(__imp_?IsTypeOf at vtkPolyDataSourceWidget@@SAHPBD at Z)
Medical1.obj : error LNK2001: unresolved external symbol "public:  
static class vtkImagePlaneWidget * __cdecl  
vtkImagePlaneWidget::New(void)" (?New at vtkImagePlaneWidget@@SAPAV1 at XZ)
Medical1.obj : error LNK2001: unresolved external symbol  
"__declspec(dllimport) public: virtual void __thiscall  
vtkPolyDataSourceWidget::PlaceWidget(void)"  
(__imp_?PlaceWidget at vtkPolyDataSourceWidget@@UAEXXZ)
Medical1.obj : error LNK2001: unresolved external symbol  
"__declspec(dllimport) public: void __thiscall  
vtkPolyDataSourceWidget:: 
PlaceWidget(float,float,float,float,float,float)"  
(__imp_?PlaceWidget at vtkPolyDataSourceWidget@@QAEXMMMMMM at Z)
Medical1.obj : error LNK2001: unresolved external symbol "public: void  
__thiscall vtkImagePlaneWidget::SetResliceInterpolate(int)"  
(?SetResliceInterpolate at vtkImagePlaneWidget@@QAEXH at Z)
Medical1.obj : error LNK2001: unresolved external symbol "public: void  
__thiscall vtkImagePlaneWidget::SetPlaneOrientation(int)"  
(?SetPlaneOrientation at vtkImagePlaneWidget@@QAEXH at Z)
Medical1.obj : error LNK2001: unresolved external symbol "public: void  
__thiscall vtkImagePlaneWidget::SetInteraction(int)"  
(?SetInteraction at vtkImagePlaneWidget@@QAEXH at Z)