Redmine

Hi, when i try to see the gantt, show me this error:

ActionView::TemplateError (undefined method `gantt_path' for #<ActionView::Base:0xbdf6294>) on line #7 of vendor/plugins/redmine_better_gantt_chart/app/views/gantts/show.html.erb:
4: <% @gantt.view = self >
5: <h2><= l(:label_gantt) ></h2>
6:
7: < form_tag(gantt_path(:month => params[:month], :year => params[:year], :months => params[:months]), :method => :put, :id => 'query_form') do >
8: <= hidden_field_tag('project_id', @project.to_param) if Herve Harster%>
9: <fieldset id="filters" class="collapsible">
10: <legend onclick="toggleFieldset(this);"><%= l(:label_filter_plural) %></legend>

vendor/plugins/redmine_better_gantt_chart/app/views/gantts/show.html.erb:7
    app/controllers/gantts_controller.rb:43
    app/controllers/gantts_controller.rb:42:in `show'
    passenger (2.2.9) lib/phusion_passenger/rack/request_handler.rb:92:in `process_request'
    passenger (2.2.9) lib/phusion_passenger/abstract_request_handler.rb:207:in `main_loop'
    passenger (2.2.9) lib/phusion_passenger/railz/application_spawner.rb:400:in `start_request_handler'
    passenger (2.2.9) lib/phusion_passenger/railz/application_spawner.rb:351:in `handle_spawn_application'
    passenger (2.2.9) lib/phusion_passenger/utils.rb:184:in `safe_fork'
    passenger (2.2.9) lib/phusion_passenger/railz/application_spawner.rb:349:in `handle_spawn_application'
    passenger (2.2.9) lib/phusion_passenger/abstract_server.rb:352:in `__send__'
    passenger (2.2.9) lib/phusion_passenger/abstract_server.rb:352:in `main_loop'
    passenger (2.2.9) lib/phusion_passenger/abstract_server.rb:196:in `start_synchronously'
    passenger (2.2.9) lib/phusion_passenger/abstract_server.rb:163:in `start'
    passenger (2.2.9) lib/phusion_passenger/railz/application_spawner.rb:209:in `start'
    passenger (2.2.9) lib/phusion_passenger/spawn_manager.rb:262:in `spawn_rails_application'
    passenger (2.2.9) lib/phusion_passenger/abstract_server_collection.rb:126:in `lookup_or_add'
    passenger (2.2.9) lib/phusion_passenger/spawn_manager.rb:256:in `spawn_rails_application'
    passenger (2.2.9) lib/phusion_passenger/abstract_server_collection.rb:80:in `synchronize'
    passenger (2.2.9) lib/phusion_passenger/abstract_server_collection.rb:79:in `synchronize'
    passenger (2.2.9) lib/phusion_passenger/spawn_manager.rb:255:in `spawn_rails_application'
    passenger (2.2.9) lib/phusion_passenger/spawn_manager.rb:154:in `spawn_application'
    passenger (2.2.9) lib/phusion_passenger/spawn_manager.rb:287:in `handle_spawn_application'
    passenger (2.2.9) lib/phusion_passenger/abstract_server.rb:352:in `__send__'
    passenger (2.2.9) lib/phusion_passenger/abstract_server.rb:352:in `main_loop'
    passenger (2.2.9) lib/phusion_passenger/abstract_server.rb:196:in `start_synchronously'

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