rake db:migrate RAILS_ENV=production にて uninitialized constant Backlogs::IssueQueryPatch::RbRelease のエラーが出る

症状

rake db:migrate RAILS_ENV=production
(in /home/redmine/redmine-2.3.1)
rake aborted!
uninitialized constant Backlogs::IssueQueryPatch::RbRelease
/home/redmine/redmine-2.3.1/plugins/redmine_backlogs-1.0.5/lib/backlogs_issue_query_patch.rb:31:in `block in included'
/home/redmine/redmine-2.3.1/plugins/redmine_backlogs-1.0.5/lib/backlogs_issue_query_patch.rb:25:in `class_eval'
/home/redmine/redmine-2.3.1/plugins/redmine_backlogs-1.0.5/lib/backlogs_issue_query_patch.rb:25:in `included'
/home/redmine/redmine-2.3.1/plugins/redmine_backlogs-1.0.5/lib/backlogs_issue_query_patch.rb:145:in `include'
/home/redmine/redmine-2.3.1/plugins/redmine_backlogs-1.0.5/lib/backlogs_issue_query_patch.rb:145:in `<top (required)>'
/home/redmine/redmine-2.3.1/plugins/redmine_backlogs-1.0.5/init.rb:27:in `block in <top (required)>'
/home/redmine/.rvm/gems/ruby-1.9.3-p286/gems/activesupport-3.2.13/lib/active_support/callbacks.rb:440:in `_run__227089559__prepare__360480817__callbacks'
/home/redmine/.rvm/gems/ruby-1.9.3-p286/gems/activesupport-3.2.13/lib/active_support/callbacks.rb:405:in `__run_callback'
/home/redmine/.rvm/gems/ruby-1.9.3-p286/gems/activesupport-3.2.13/lib/active_support/callbacks.rb:385:in `_run_prepare_callbacks'
/home/redmine/.rvm/gems/ruby-1.9.3-p286/gems/activesupport-3.2.13/lib/active_support/callbacks.rb:81:in `run_callbacks'
/home/redmine/.rvm/gems/ruby-1.9.3-p286/gems/actionpack-3.2.13/lib/action_dispatch/middleware/reloader.rb:74:in `prepare!'
/home/redmine/.rvm/gems/ruby-1.9.3-p286/gems/actionpack-3.2.13/lib/action_dispatch/middleware/reloader.rb:48:in `prepare!'
/home/redmine/.rvm/gems/ruby-1.9.3-p286/gems/railties-3.2.13/lib/rails/application/finisher.rb:47:in `block in <module:Finisher>'
/home/redmine/.rvm/gems/ruby-1.9.3-p286/gems/railties-3.2.13/lib/rails/initializable.rb:30:in `instance_exec'
/home/redmine/.rvm/gems/ruby-1.9.3-p286/gems/railties-3.2.13/lib/rails/initializable.rb:30:in `run'
/home/redmine/.rvm/gems/ruby-1.9.3-p286/gems/railties-3.2.13/lib/rails/initializable.rb:55:in `block in run_initializers'
/home/redmine/.rvm/gems/ruby-1.9.3-p286/gems/railties-3.2.13/lib/rails/initializable.rb:54:in `each'
/home/redmine/.rvm/gems/ruby-1.9.3-p286/gems/railties-3.2.13/lib/rails/initializable.rb:54:in `run_initializers'
/home/redmine/.rvm/gems/ruby-1.9.3-p286/gems/railties-3.2.13/lib/rails/application.rb:136:in `initialize!'
/home/redmine/.rvm/gems/ruby-1.9.3-p286/gems/railties-3.2.13/lib/rails/railtie/configurable.rb:30:in `method_missing'
/home/redmine/redmine-2.3.1/config/environment.rb:14:in `<top (required)>'
/home/redmine/.rvm/gems/ruby-1.9.3-p286/gems/railties-3.2.13/lib/rails/application.rb:103:in `require'
/home/redmine/.rvm/gems/ruby-1.9.3-p286/gems/railties-3.2.13/lib/rails/application.rb:103:in `require_environment!'
/home/redmine/.rvm/gems/ruby-1.9.3-p286/gems/railties-3.2.13/lib/rails/application.rb:297:in `block (2 levels) in initialize_tasks'
/home/redmine/.rvm/gems/ruby-1.9.3-p286/bin/ruby_noexec_wrapper:14:in `eval'
/home/redmine/.rvm/gems/ruby-1.9.3-p286/bin/ruby_noexec_wrapper:14:in `<main>'
Tasks: TOP => db:migrate => environment
(See full trace by running task with --trace)

対処

cd plugins

        mv redmine_backlogs-1.0.5 redmine_backlogs