Installing on Ubuntu 12.04

I've had great success installing xfpa on Ubuntu in the last year by ensuring the following packages are installed:
git-core
libxml2-dev
libmotif-dev
gfortran
libpng-dev
libjpeg-dev
libtiff4-dev
libx11-dev
libxt-dev
libxft-dev
libxmu-dev
libxpm-dev
libgrib2c-dev
libjasper-dev

apt-get install libxml2-dev libmotif-dev gfortran libpng-dev libjpeg-dev libtiff4-dev libx11-dev libxt-dev libxft-dev libxmu-dev libxpm-dev libgrib2c-dev libjasper-dev

Then download and compile as directed in the admin manual chapter 3.

EDIT 2016-10-26
It is no longer necessary to compile in 32bit on a 64bit machine (unless you want to use the GRIB1 decoder but why would you?) With the above packages installed (libmotif-dev, libjasper and libgrib2c) compilation is a lot easier. You can skip the section that calls for installing those manually.