Dear Daniel,
If you are trying to make LAMMPS in Ubuntu, try these steps
Open up a terminal and type
sudo apt-get install build-essential mpich-bin libmpich1.0-dev mpi-doc fftw2 fftw-dev libxaw7-dev
Then open up the src directory and type
make debian
This should solve your issue.It worked well for me.
Thanks to Yoshis88, who originally posted this in the Ubuntu Forums
Hope this solves your problem
Regards,
Nandu Gopan