To install Doctrine via SVN is very easy. You can download any version of Doctrine from the SVN server: http://svn.doctrine-project.org
To check out a specific version you can use the following command from your terminal:
svn co http://svn.doctrine-project.org/branches/1.2 .
If you do not have a SVN client, chose one from the list below. Find the Checkout option and enter http://svn.doctrine-project.org/branches/1.2 in the path or repository url parameter. There is no need for a username or password to check out Doctrine.