Redmine

After refering to the correct versions of rails and rack supported by redmine on http://www.redmine.org/projects/redmine/wiki/RedmineInstall
for redmine 1.2.1, i run following

sudo gem install rails -v=2.3.11
sudo gem install rack -v=1.1.0

now
i18n (0.5.0, 0.4.2)
rack (1.2.3, 1.1.2, 1.1.0)
rails (3.0.9, 2.3.11)
rake (0.9.2)
rubygems-update (1.8.6)

but still i get the same error

You shouldn't run the rake tasks with "sudo". And you could provide the trace of the task when adding a --trace option to the rake task, could be useful...

http://www.redmine.org/projects/redmine/wiki/RedmineInstall says that you need rake 0.8.7. You're using 0.8.3/0.9.2.

Try gem install rake -v 0.8.7