First download the [[OpenPetra]] source code by running `bzr branch lp:openpetraorg`. This might take up to 40 minutes depending on the connection speed.
If you're having issues related to the crossdomainmarshaller you have to [install a patch](http://software.opensuse.org/download.html?project=home%3Atpokorra%3Aopenpetra&package=mono-openpetra).
sudo su -c "echo 'deb http://download.opensuse.org/repositories/home:tpokorra:openpetra/xUbuntu_12.04/ /' >> /etc/apt/sources.list.d/mono-openpetra.list"
- <https://github.com/openpetra/openpetra/blob/master/setup/petra0300/linuxserver/INSTALL>, or up to date <https://github.com/tpokorra/openpetragit/blob/feature2013_09_remoting/setup/petra0300/linuxserver/INSTALL>