Redmine

hello,
i have a problem with the installation of an addon.

some system-informations:

Distribution: Debian Squeeze
Redmine: 1.0.1-2
actionmailer (2.3.11)
actionpack (2.3.11)
activerecord (2.3.11)
activeresource (2.3.11)
activesupport (2.3.11)
rack (1.1.3)
rails (2.3.11)
rake (0.9.2.2)
rubygems-update (1.8.5)

i want to install the work_time addon, so i downloaded the .zip and copied it to /usr/share/redmine/vendor/plugins.
now run RAILS_ENV=production rake db:migrate:plugin NAME=redmine_work_time and get the following error: rake aborted!
uninitialized constant RedmineApp

when i run RAILS_ENV=production rake --trace db:migrate:plugin NAME=redmine_work_time i get this:

@(in /usr/share/redmine)
WARNING: 'rdoc/task' is deprecated. Please use 'require 'rdoc/task' (in RDoc 2.4.2+)' instead.
at /usr/lib/ruby/gems/1.8/gems/rake-0.9.2.2/lib/rake/rdoctask.rb

• Invoke db:migrate:plugin (first_time)
• Invoke environment (first_time)
• Execute environment
  rake aborted!
  uninitialized constant RedmineApp
  /usr/lib/ruby/1.8/active_support/dependencies.rb:443:in `load_missing_constant'
  /usr/lib/ruby/1.8/active_support/dependencies.rb:80:in `const_missing'
  /usr/lib/ruby/1.8/active_support/dependencies.rb:92:in `const_missing'
  /usr/share/redmine/vendor/plugins/redmine_work_time/config/routes.rb:1
  /usr/lib/ruby/1.8/active_support/dependencies.rb:147:in `load_without_new_constant_marking'
  /usr/lib/ruby/1.8/active_support/dependencies.rb:147:in `load'
  /usr/lib/ruby/1.8/action_controller/routing/route_set.rb:286:in `load_routes!'
  /usr/lib/ruby/1.8/action_controller/routing/route_set.rb:286:in `each'
  /usr/lib/ruby/1.8/action_controller/routing/route_set.rb:286:in `load_routes!'
  /usr/lib/ruby/1.8/action_controller/routing/route_set.rb:266:in `reload!'
  /usr/share/redmine/config/../vendor/rails/railties/lib/initializer.rb:537:in `initialize_routing'
  /usr/share/redmine/config/../vendor/rails/railties/lib/initializer.rb:188:in `process'
  /usr/share/redmine/config/../vendor/rails/railties/lib/initializer.rb:113:in `send'
  /usr/share/redmine/config/../vendor/rails/railties/lib/initializer.rb:113:in `run'
  /usr/share/redmine/config/environment.rb:57
  /usr/local/lib/site_ruby/1.8/rubygems/custom_require.rb:29:in `gem_original_require'
  /usr/local/lib/site_ruby/1.8/rubygems/custom_require.rb:29:in `require'
  /usr/lib/ruby/1.8/active_support/dependencies.rb:156:in `require'
  /usr/lib/ruby/1.8/active_support/dependencies.rb:521:in `new_constants_in'
  /usr/lib/ruby/1.8/active_support/dependencies.rb:156:in `require'
  /usr/share/redmine/vendor/rails/railties/lib/tasks/misc.rake:4
  /usr/lib/ruby/gems/1.8/gems/rake-0.9.2.2/lib/rake/task.rb:205:in `call'
  /usr/lib/ruby/gems/1.8/gems/rake-0.9.2.2/lib/rake/task.rb:205:in `execute'
  /usr/lib/ruby/gems/1.8/gems/rake-0.9.2.2/lib/rake/task.rb:200:in `each'
  /usr/lib/ruby/gems/1.8/gems/rake-0.9.2.2/lib/rake/task.rb:200:in `execute'
  /usr/lib/ruby/gems/1.8/gems/rake-0.9.2.2/lib/rake/task.rb:158:in `invoke_with_call_chain'
  /usr/lib/ruby/1.8/monitor.rb:242:in `synchronize'
  /usr/lib/ruby/gems/1.8/gems/rake-0.9.2.2/lib/rake/task.rb:151:in `invoke_with_call_chain'
  /usr/lib/ruby/gems/1.8/gems/rake-0.9.2.2/lib/rake/task.rb:176:in `invoke_prerequisites'
  /usr/lib/ruby/gems/1.8/gems/rake-0.9.2.2/lib/rake/task.rb:174:in `each'
  /usr/lib/ruby/gems/1.8/gems/rake-0.9.2.2/lib/rake/task.rb:174:in `invoke_prerequisites'
  /usr/lib/ruby/gems/1.8/gems/rake-0.9.2.2/lib/rake/task.rb:157:in `invoke_with_call_chain'
  /usr/lib/ruby/1.8/monitor.rb:242:in `synchronize'
  /usr/lib/ruby/gems/1.8/gems/rake-0.9.2.2/lib/rake/task.rb:151:in `invoke_with_call_chain'
  /usr/lib/ruby/gems/1.8/gems/rake-0.9.2.2/lib/rake/task.rb:144:in `invoke'
  /usr/lib/ruby/gems/1.8/gems/rake-0.9.2.2/lib/rake/application.rb:116:in `invoke_task'
  /usr/lib/ruby/gems/1.8/gems/rake-0.9.2.2/lib/rake/application.rb:94:in `top_level'
  /usr/lib/ruby/gems/1.8/gems/rake-0.9.2.2/lib/rake/application.rb:94:in `each'
  /usr/lib/ruby/gems/1.8/gems/rake-0.9.2.2/lib/rake/application.rb:94:in `top_level'
  /usr/lib/ruby/gems/1.8/gems/rake-0.9.2.2/lib/rake/application.rb:133:in `standard_exception_handling'
  /usr/lib/ruby/gems/1.8/gems/rake-0.9.2.2/lib/rake/application.rb:88:in `top_level'
  /usr/lib/ruby/gems/1.8/gems/rake-0.9.2.2/lib/rake/application.rb:66:in `run'
  /usr/lib/ruby/gems/1.8/gems/rake-0.9.2.2/lib/rake/application.rb:133:in `standard_exception_handling'
  /usr/lib/ruby/gems/1.8/gems/rake-0.9.2.2/lib/rake/application.rb:63:in `run'
  /usr/lib/ruby/gems/1.8/gems/rake-0.9.2.2/bin/rake:33
  /usr/local/bin/rake:19:in `load'
  /usr/local/bin/rake:19
  Tasks: TOP => db:migrate:plugin => environment@

can pls anybody help me fix that problem?