In fact, there are some points leading us to find something better than make :
dependencies are not easy to maintain in a makefile, mainly in C++ where the change of a class can lead to a lot of recompilation, and this is not easily maintainable with makefiles. I know that this kind of thing can be done with the GNU build system, but if we have to take some advanced tool, let's go for something really powerful and extensible
our component will use other components, which in turn use other components. For one version of our software, we need to define the version of sub-components to use, and this is easily done with something like Scons
a more advanced tool like Scons can grab automatically the source from CVS, which save us one manual step in the process. This is built-in in the tool.
a complex but extensible tool is always an investment for the future, as we don't know yet what specific steps will have to be done during the build of our soft, and having the power of Python (or Perl) to script some advanced build step will give us room for improvement.