[vtkusers] Adding class to vtk source install

[Wolfram H Volpi]

This is my first source install.  
I added a new class and then call it from a tcl script.
Please help me solve the "invalid command name" error:

Error in startupscript 
! invalid command name "vtkMyNewClass"
    while executing "vtkMyNewClass myObject"

How do I trouble shot this? 

Thank you for your help,
Wolf.

Below is what I did (in sequence):


vtk3.1 source install on NT 4.0 with MS VC++ 6.0 compiler.

Added new class to D:\vtk31CD\vtk\local\
  vtkVolumPropertyCubic.h
  vtkVolumPropertyCubic.cxx

Added class to D:\vtk31CD\vtk\local\Makefile.in 
 CONCRTETE = \
 vtkVolumePropertyCubic

clicked on D:\vtk31CD\vtk\pcmaker\cpmaker.exe
  OK

>From MSDOS Command Prompt C:\vtkbin\Debug>nmake

clicked on D:\My Documents\MRI\volCubic\volCubic.tcl

OS Error in startupscript 
! invalid command name "vtkVolumePropertyCubic"
    while executing "vtkVolumePropertyCubic io_prop"