Unable to link to VTK library

The project I'm working on fails to link properly. It is built with CMAKE & GNU C/C++ compilers. It use to compile & link fine, before the PC got updated(Buntu11.04 to 12.04, installed packages updated as well). The projects VTK is ver 5.8.0. (Builds w/o err's.) This is the same version that was used B/4 the update.

The err is: undefined reference to QVTKWidget2::QVTKWidget(QWidget*, QGLWidget const*, QFlags) This is a call to VTK/GUISupport/Qt/QVTKWidget2.cxx. From here I'm lost. I don't know which library is missing. i.e. Which lib has the QVTKWidget2 class? How do I find this?

I'm not sure if I'm looking for a libSomeNAme.so or libSomeName.a file.