Redmine

Hello everyone, I have trouble since I upgrade the ubuntu on which the redmine run.
The ubuntu have been upgrade from 11.04 to 11.10. all is ok.
Now the server side is almost good, apache run perfectly, I have kimai for tracking hours, all is good.
But on the redmine I have 2 problems : when I acces on a project page by the normal way I have a error500.When I access to a project page by the admin way/project all is ok, I can see the project in "setting" mode
The second things is that I no longer send mail from redmine.
So I have read the log files and this is what's appears when the 500 error occured :

ActionView::TemplateError (undefined method `visible?' for #<ActiveRecord::Associations::BelongsToAssociation:0xb6059dec>) on line #19 of app/views/projects/show.rhtml:
16:      <li><%=l(:label_subproject_plural)%>:
17:         <%= @subprojects.collect{|p| link_to(h(p), :action => 'show', :id => p)}.join(", ") %></li>
18:   <% end %>
19:     <% @project.visible_custom_field_values.each do |custom_value| %>
20:     <% if !custom_value.value.blank? %>
21:        <li><%= custom_value.custom_field.name%>: <%=h show_value(custom_value) %></li>
22:     <% end %>

    /usr/lib/ruby/vendor_ruby/active_record/associations/association_proxy.rb:217:in `method_missing'
    app/models/custom_value.rb:38:in `visible?'
    /usr/lib/ruby/vendor_ruby/action_view/renderable.rb:91:in `to_proc'
    app/views/projects/show.rhtml:19:in `_run_rhtml_app47views47projects47show46rhtml'
    /usr/lib/ruby/vendor_ruby/action_view/renderable.rb:34:in `send'
    /usr/lib/ruby/vendor_ruby/action_view/renderable.rb:34:in `render'
    /usr/lib/ruby/vendor_ruby/action_view/base.rb:306:in `with_template'
    /usr/lib/ruby/vendor_ruby/action_view/renderable.rb:30:in `render'
    /usr/lib/ruby/vendor_ruby/action_view/template.rb:205:in `render_template'
    /usr/lib/ruby/vendor_ruby/action_view/base.rb:265:in `render'
    /usr/lib/ruby/vendor_ruby/action_view/base.rb:348:in `_render_with_layout'
    /usr/lib/ruby/vendor_ruby/action_view/base.rb:262:in `render'
    /usr/lib/ruby/vendor_ruby/action_controller/base.rb:1252:in `render_for_file'
    /usr/lib/ruby/vendor_ruby/action_controller/base.rb:942:in `render_without_benchmark'
    /usr/lib/ruby/vendor_ruby/action_controller/benchmarking.rb:51:in `render'
    /usr/lib/ruby/vendor_ruby/action_controller/benchmarking.rb:51:in `render'
    /usr/lib/ruby/vendor_ruby/action_controller/mime_responds.rb:135:in `send'
    /usr/lib/ruby/vendor_ruby/action_controller/mime_responds.rb:135:in `custom'
    /usr/lib/ruby/vendor_ruby/action_controller/mime_responds.rb:179:in `call'
    /usr/lib/ruby/vendor_ruby/action_controller/mime_responds.rb:179:in `respond'
    /usr/lib/ruby/vendor_ruby/action_controller/mime_responds.rb:173:in `each'
    /usr/lib/ruby/vendor_ruby/action_controller/mime_responds.rb:173:in `respond'
    /usr/lib/ruby/vendor_ruby/action_controller/mime_responds.rb:107:in `respond_to'
    app/controllers/projects_controller.rb:165:in `show'
    /usr/lib/ruby/vendor_ruby/action_controller/base.rb:1333:in `send'
    /usr/lib/ruby/vendor_ruby/action_controller/base.rb:1333:in `perform_action_without_filters'
    /usr/lib/ruby/vendor_ruby/action_controller/filters.rb:617:in `call_filters'
    /usr/lib/ruby/vendor_ruby/action_controller/filters.rb:610:in `perform_action_without_benchmark'
    /usr/lib/ruby/vendor_ruby/action_controller/benchmarking.rb:68:in `perform_action_without_rescue'
    /usr/lib/ruby/vendor_ruby/action_controller/benchmarking.rb:68:in `perform_action_without_rescue'
    /usr/lib/ruby/vendor_ruby/action_controller/rescue.rb:160:in `perform_action_without_flash'
    /usr/lib/ruby/vendor_ruby/action_controller/flash.rb:151:in `perform_action'
    /usr/lib/ruby/vendor_ruby/action_controller/base.rb:532:in `send'
    /usr/lib/ruby/vendor_ruby/action_controller/base.rb:532:in `process_without_filters'
    /usr/lib/ruby/vendor_ruby/action_controller/filters.rb:606:in `process'
    /usr/lib/ruby/vendor_ruby/action_controller/base.rb:391:in `process'
    /usr/lib/ruby/vendor_ruby/action_controller/base.rb:386:in `call'
    /usr/lib/ruby/vendor_ruby/action_controller/routing/route_set.rb:438:in `call'
    /usr/lib/ruby/vendor_ruby/action_controller/dispatcher.rb:87:in `dispatch'
    /usr/lib/ruby/vendor_ruby/action_controller/dispatcher.rb:121:in `_call'
    /usr/lib/ruby/vendor_ruby/action_controller/dispatcher.rb:130:in `build_middleware_stack'
    /usr/lib/ruby/vendor_ruby/active_record/query_cache.rb:29:in `call'
    /usr/lib/ruby/vendor_ruby/active_record/query_cache.rb:29:in `call'
    /usr/lib/ruby/vendor_ruby/active_record/connection_adapters/abstract/query_cache.rb:34:in `cache'
    /usr/lib/ruby/vendor_ruby/active_record/query_cache.rb:9:in `cache'
    /usr/lib/ruby/vendor_ruby/active_record/query_cache.rb:28:in `call'
    /usr/lib/ruby/vendor_ruby/active_record/connection_adapters/abstract/connection_pool.rb:361:in `call'
    /usr/lib/ruby/vendor_ruby/action_controller/string_coercion.rb:25:in `call'
    /usr/lib/ruby/1.8/rack/head.rb:9:in `call'
    /usr/lib/ruby/1.8/rack/methodoverride.rb:24:in `call'
    /usr/lib/ruby/vendor_ruby/action_controller/params_parser.rb:15:in `call'
    /usr/lib/ruby/vendor_ruby/action_controller/session/cookie_store.rb:99:in `call'
    /usr/lib/ruby/vendor_ruby/action_controller/failsafe.rb:26:in `call'
    /usr/lib/ruby/1.8/rack/lock.rb:11:in `call'
    /usr/lib/ruby/1.8/rack/lock.rb:11:in `synchronize'
    /usr/lib/ruby/1.8/rack/lock.rb:11:in `call'
    /usr/lib/ruby/vendor_ruby/action_controller/dispatcher.rb:106:in `call'
    /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 /usr/share/redmine/public/500.html (500 Internal Server Error)

and this is the details of the redmine&co :

About your application's environment

Ruby version              1.8.7 (i686-linux)
RubyGems version          1.7.2
Rack version              1.1
Rails version             2.3.14
Active Record version     2.3.14
Active Resource version   2.3.14
Action Mailer version     2.3.14
Active Support version    2.3.14
Edge Rails revision       unknown
Application root          /usr/share/redmine
Environment               production
Database adapter          mysql
Database schema version   20100819172912

About your Redmine plugins
Redmine Ultraviolet Syntax highlighting plugin   0.0.3
SCM Creator                                      0.1.1
Extended profile                                 0.0.2