Redmine › Extended Fields

When I install this plugin and Extended Profile I’m getting an internal error trying to add or edit an custom field, here is the log...

Processing by CustomFieldsController#new as HTML
  Parameters: {"type"=>"IssueCustomField"}
  Current user: doropeza (id=3)
  Rendered plugins/extended_fields/app/views/custom_fields/_extended.html.erb (9.0ms)
  Rendered custom_fields/_form.html.erb (25.5ms)
  Rendered custom_fields/new.html.erb within layouts/admin (36.1ms)
Completed 500 Internal Server Error in 105ms

ActionView::Template::Error (wrong number of arguments (1 for 0)):
    1: <% projects = Project.all_public.active(:order => 'name').collect{ |project| [ project.name, project.id ] } %>
    2: 
    3: <% unless defined? observe_field %>
    4: 
  app/models/project.rb:91:in `block in <class:Project>'
  lib/redmine/hook.rb:111:in `block in render_on'
  lib/redmine/hook.rb:61:in `block (2 levels) in call_hook'
  lib/redmine/hook.rb:61:in `each'
  lib/redmine/hook.rb:61:in `block in call_hook'
  lib/redmine/hook.rb:58:in `tap'
  lib/redmine/hook.rb:58:in `call_hook'
  lib/redmine/hook.rb:158:in `call_hook'
  app/views/custom_fields/_form.html.erb:43:in `_app_views_custom_fields__form_html_erb___184421173_103293260'
  app/views/custom_fields/new.html.erb:6:in `block in _app_views_custom_fields_new_html_erb___975800513_102558610'
  app/helpers/application_helper.rb:944:in `labelled_form_for'
  app/views/custom_fields/new.html.erb:5:in `_app_views_custom_fields_new_html_erb___975800513_102558610'

I have a redmine cloned & updated proyect from github.