[vtkusers] build fail - nightly 6/11 on WinNT

[anast.jm at pg.com]

Has anyone else seen this build error or could add some insight?? The dashboard
looked clean for NT...john

E:\WinCVS\vtk\contrib\vtkXYPlotActor.cxx(1523) : error C2440: 'initializing' : cannot convert from 'class vtkDataArray *' to 'class vtkNormals *'
        Types pointed to are unrelated; conversion requires reinterpret_cast, C-style cast or function-style cast
E:\WinCVS\vtk\contrib\vtkXYPlotActor.cxx(1652) : error C2039: 'GetNormal' : is not a member of 'vtkDataArray'
        E:\WinCVS\vtk\common\vtkDataArray.h(79) : see declaration of 'vtkDataArray'
NMAKE : fatal error U1077: 'cl.exe' : return code '0x2'
Stop.
NMAKE : fatal error U1077: '"C:\Program Files\Microsoft Visual Studio\VC98\bin\NMAKE.EXE"' : return code '0x2'
Stop.