If NumPy isn't reporting a LAPACK and a LAPACK exists on the system that you intend to use, you misconfigured NumPy.  I never put LAPACK/BLAS detection into PyClaw, and it was never my intention to do anything but reuse NumPy's installation configuration for both the Fortran compiler and the LAPACK/BLAS libraries.  Putting default flags there is dangerous in a number of ways.