Just installed Mapnik on the iNat slice at Slicehost, which runs Ubuntu Hardy (8.04). Since the process was not exactly trivial, here’s what I ended up doing:

# Get up to date and install deps
# Docs: http://trac.mapnik.org/wiki/UbuntuInstallationOld
aptitude update
aptitude install binutils cpp-3.3 g++-3.3 gcc-3.3 gcc-3.3-base libboost-dev libboost-filesystem-dev libboost-filesystem1.34.1 libboost-iostreams-dev libboost-iostreams1.34.1 libboost-program-options-dev libboost-program-options1.34.1 libboost-python-dev libboost-python1.34.1 libboost-regex-dev libboost-regex1.34.1 libboost-serialization-dev libboost-serialization1.34.1 libboost-thread-dev libboost-thread1.34.1 libicu-dev libicu38 libstdc++5 libstdc++5-3.3-dev python2.5-dev
aptitude install libfreetype6 libfreetype6-dev libjpeg62 libjpeg62-dev libltdl3 libltdl3-dev libpng12-0 libpng12-dev libtiff4 libtiff4-dev libtiffxx0c2 python-imaging python-imaging-dbg proj
aptitude install libcairo2 libcairo2-dev python-cairo python-cairo-dev libcairomm-1.0-1 libcairomm-1.0-dev libglib2.0-0 libpixman-1-0 libpixman-1-dev libpthread-stubs0 libpthread-stubs0-dev ttf-dejavu ttf-dejavu-core ttf-dejavu-extra
aptitude install libgdal-dev python2.5-gdal
aptitude install libxslt1.1 libxslt1-dev libxml2-dev libxml2
easy_install jonpy
easy_install lxml
# Configure and instlall mapnik from source
# Docs: http://trac.mapnik.org/wiki/UsingScons
python scons/scons.py configure INPUT_PLUGINS=shape,gdal,ogr,sqlite
python scons/scons.py
python scons/scons.py install
# Make sure ld knows where to find the new libs
# Thanks to http://www.drazzib.com/projets:openstreetmap:postgis_mapnik_tile_server
echo "/usr/local/lib64" >> /etc/ld.so.conf.d/local.conf

My main mistake was thinking that the python-mapnik package in Aptitude was going to cut mustard. Didn’t even include OGR support! Luckily the most recent Mapnik release (0.6.1) built just fine. Still easier that installing under OS X.