Apparently, my problem is that I need to use dmcs instead on 12.04. Starting from Mono 2.11, there will be a unified compiler command mcs. Thanks. -- View this message in context: http://mono.1490590.n4.nabble.com/mono-on-ubuntu-12-04-LTS-tp4658092p4658095.html Sent from the Mono - General mailing list archive at Nabble.com.