fft3d.h(164): catastrophic error: could not open source file "fftw.h"

I was compiling LAMMPS Molecular Dynamics Simulator.

1. Using $SOURCE/lammps-30Mar10/src
2. I compiled using make.linux. Quite soon, I encounter the following error fft3d.h(164): catastrophic error: could not open source file "fftw.h"
3. I have compiled my fftw3 and my Intel Math Kernel library properly and was able to locate the header in my Intel Math Kernel Library. I've correctly "source" the path at LD_LIBRARY_PATH and /etc/ld.so.conf.d. But the LAMMPS is still not able to locate the library.
4. I realise the cruz of the problem was that LAMPS requires FFTW-2.1.x. configuring and compiling fftw-2.x, the problem went away

Problem eliminated. My compilation is not done yet. But this fftw initial problem is settle for now :)