The very first factor you want to do is try looking in your log/production.log file inside your live application directory. Which will contain all of the relevant particulars about your error.
You will find certain - very helpful - plug ins (exception_notification for instance) that will email particulars about errors for you because they occur.
- book your database.yml.
- see log: log/development.log
- you are able to debug problem: http://bashdb.sourceforge.internet/ruby-debug.html
hope useful along with you!
The most recent Redmine trunk operates on Rails 2.3.5
that could be leading to you problems. Try setting RAILS_Jewel_VERSION = '2.3.8' inside your atmosphere.rb file... while you might find other bugs appear!