Some month ago I installed Redmine from repository using apt-get install redmine. I didn't know much about redmine so I just followed a guide, created a MySql DB and a user and installed it. Version is 1.3.2
Later on I wanted to install some plugins and see that most of them require redmine 1.4.x
So I thought about upgrading, but this is the latest repository file. Is there a "safe" way to upgrade redmine to a newer version?
Server is running Ubuntu 12.04