Since Ruby 1.9.2, LOAD_PATH does not include "." directory anymore, so
we should use absolute paths instead to ensure both 1.8.x and 1.9.x
compatibility. It has been included in railties 2.3.x branch since
july 2009, see 7a427a83ca
git-svn-id: svn+ssh://rubyforge.org/var/svn/redmine/trunk@4359 e93f8b46-1217-0410-a6f0-8f06a7374b81