[vtkusers] Building VTK with QtSDK

[Gib Bogle]

I'm building VTK + VTK_USE_QT on Windows with QtSDK-4.7.3.  This is the first 
time I've tried to build VTK using the Qt SDK.  cmake-gui gives an error 
message:  Could not find Qt4.
I have set the environment variable QTDIR, and added %QTDIR%\bin to the PATH.
I have other programs that I build using Qt on this machine, but for these I am 
using QtCreator - which obviously knows where to find Qt4.

Can someone tell me what I need to do to ensure that Qt4 is found by cmake-gui 
(i.e. by cmake's FIND_PACKAGE()) when using QtSDK?

Thanks
Gib