Cannot add new issue to user story in next sprint

[Rzulf]

Adding new issues to user story doesn't work through dashboard. I worked for sprints 1-6 but for 7 it doesn't. Here is stackstrace

Processing IssueSprintsController#new (for 95.40.221.243 at 2011-01-24 20:53:32) [POST]
Parameters: {"user_story_id"=>"180", "commit"=>"Dodaj", "project_id"=>"mohavi", "action"=>"new", "authenticity_token"=>"LlP6hlkXNjLS5LXY2EYf9kQmU1Z8W1OVSbRituc9M8k=", "issue"=>{"start_date"=>"2011-01-24", "custom_field_values"=>{"2"=>""}, "estimated_hours"=>"", "user_story_id"=>"180", "priority_id"=>"5", "done_ratio"=>"0", "assigned_to_id"=>"3", "subject"=>"Formularz dodawania nowego paragonu", "tracker_id"=>"2", "due_date"=>"", "status_id"=>"1", "description"=>""}, "controller"=>"issue_sprints", "attachments"=>{"1"=>{"description"=>""}}, "_"=>""}
Rendering template within layouts/base
Rendering issue_sprints/new

ActionView::TemplateError (undefined method `collect' for nil:NilClass) on line #24 of vendor/plugins/redmine_sprints/app/views/issue_sprints/_form.rhtml:
21:

<%= l(:field_status) %> <%= @issue.status.name %>

22: <% end %>
23:
24:

<%= f.select :priority_id, (@priorities.collect {|p| [p.name, p.id]}), :required => true %>

25:

<%= f.select :assigned_to_id, (@issue.assignable_users.collect {|m| [m.name, m.id]}), :include_blank => true %>

26: <% unless @project.issue_categories.empty? %>
27:

<%= f.select :category_id, (@project.issue_categories.collect {|c| [c.name, c.id]}), :include_blank => true %>

vendor/plugins/redmine_sprints/app/views/issue_sprints/_form.rhtml:24:in `_run_rhtml_vendor47plugins47redmine_sprints47app47views47issue_sprints47_form46rhtml_locals_f_form_object'
vendor/plugins/redmine_sprints/app/views/issue_sprints/new.rhtml:8:in `_run_rhtml_vendor47plugins47redmine_sprints47app47views47issue_sprints47new46rhtml'
vendor/plugins/redmine_sprints/app/helpers/sprints_helper.rb:128:in `labelled_tabular_remote_form_for'
vendor/plugins/redmine_sprints/app/views/issue_sprints/new.rhtml:3:in `_run_rhtml_vendor47plugins47redmine_sprints47app47views47issue_sprints47new46rhtml'
/usr/lib/ruby/1.8/phusion_passenger/rack/request_handler.rb:92:in `process_request'
/usr/lib/ruby/1.8/phusion_passenger/abstract_request_handler.rb:207:in `main_loop'
/usr/lib/ruby/1.8/phusion_passenger/railz/application_spawner.rb:418:in `start_request_handler'
/usr/lib/ruby/1.8/phusion_passenger/railz/application_spawner.rb:358:in `handle_spawn_application'
/usr/lib/ruby/1.8/phusion_passenger/utils.rb:184:in `safe_fork'
/usr/lib/ruby/1.8/phusion_passenger/railz/application_spawner.rb:354:in `handle_spawn_application'
/usr/lib/ruby/1.8/phusion_passenger/abstract_server.rb:352:in `__send__'
/usr/lib/ruby/1.8/phusion_passenger/abstract_server.rb:352:in `main_loop'
/usr/lib/ruby/1.8/phusion_passenger/abstract_server.rb:196:in `start_synchronously'
/usr/lib/ruby/1.8/phusion_passenger/abstract_server.rb:163:in `start'
/usr/lib/ruby/1.8/phusion_passenger/railz/application_spawner.rb:213:in `start'
/usr/lib/ruby/1.8/phusion_passenger/spawn_manager.rb:262:in `spawn_rails_application'
/usr/lib/ruby/1.8/phusion_passenger/abstract_server_collection.rb:126:in `lookup_or_add'
/usr/lib/ruby/1.8/phusion_passenger/spawn_manager.rb:256:in `spawn_rails_application'
/usr/lib/ruby/1.8/phusion_passenger/abstract_server_collection.rb:80:in `synchronize'
/usr/lib/ruby/1.8/phusion_passenger/abstract_server_collection.rb:79:in `synchronize'
/usr/lib/ruby/1.8/phusion_passenger/spawn_manager.rb:255:in `spawn_rails_application'
/usr/lib/ruby/1.8/phusion_passenger/spawn_manager.rb:154:in `spawn_application'
/usr/lib/ruby/1.8/phusion_passenger/spawn_manager.rb:287:in `handle_spawn_application'
/usr/lib/ruby/1.8/phusion_passenger/abstract_server.rb:352:in `__send__'
/usr/lib/ruby/1.8/phusion_passenger/abstract_server.rb:352:in `main_loop'
/usr/lib/ruby/1.8/phusion_passenger/abstract_server.rb:196:in `start_synchronously'
/usr/lib/phusion_passenger/passenger-spawn-server:61

Rendering /home/redmine/www/public/500.html (500 Internal Server Error)