How to install Mediawiki

install the following packages
apt-get install git php5-mysql mysql-server php5-cli php5  libapache2-mod-php5 php-apc php5-intl imagemagick
download it via git from gerrit
git clone https://gerrit.wikimedia.org/r/p/mediawiki/core.git

now the math extension can be enabled via the following procedure
go to extensions
download math extension from git
switch to LaTeXML branch
see
http://www.mediawiki.org/wiki/Extension:Math
enable extension in localsettings
run update script

Comments

submodules

you can install the submodules via
git submodule update --init

current version

I recommend to the current deployment branch wmf/1.21wmf9.