[Alumnionrails-errors] [ALI] user#edit (ActionController::DoubleRenderError) "Can only render or redirect once per action"

[Application Error]

A ActionController::DoubleRenderError occurred in user#edit:

  Can only render or redirect once per action
  /usr/local/lib/ruby/gems/1.8/gems/actionpack-1.13.3/lib/action_controller/base.rb:708:in `render_with_no_layout'

-------------------------------
Request:
-------------------------------

  * URL: http://ali.ba-ravensburg.de/user/edit/20
  * Parameters: {"action"=>"edit", "id"=>"20", "controller"=>"user"}
  * Rails root: .

-------------------------------
Session:
-------------------------------

  * session id: "12d2d93889046e1102913517712d5b2b"
  * data: {:requested_uri=>"/user/edit/20",
     "flash"=>{:notice=>"Für diese Aktion hast du keine Berechtigung."}}

-------------------------------
Environment:
-------------------------------

  * CONTENT_LENGTH      : 0
  * DOCUMENT_ROOT       : /var/www/localhost/rails/alumnionrails/current/public
  * HTTP_ACCEPT         : text/html, text/plain, text/xml, application/pdf, application/msword, application/vnd.ms-excel, application/mspowerpoint, application/postscript
  * HTTP_ACCEPT_LANGUAGE: en
  * HTTP_HOST           : ali.ba-ravensburg.de
  * HTTP_USER_AGENT     : Snapbot/1.0 (Snap Shots, +http://www.snap.com)
  * PATH_INFO           : /user/edit/20
  * QUERY_STRING        : 
  * REMOTE_ADDR         : 38.98.19.67
  * REMOTE_PORT         : 52061
  * REQUEST_METHOD      : GET
  * REQUEST_URI         : /user/edit/20
  * SCGI                : 1
  * SCRIPT_NAME         : 
  * SERVER_ADDR         : 141.68.102.148
  * SERVER_ADMIN        : m at rceldevantier.de
  * SERVER_NAME         : ali.ba-ravensburg.de
  * SERVER_PORT         : 80
  * SERVER_PROTOCOL     : HTTP/1.0
  * SERVER_SOFTWARE     : Apache
  * UNIQUE_ID           : MOirw41EZpQAAGaEI30AAAAK
  
  * Process: 3166
  * Server :

-------------------------------
Backtrace:
-------------------------------

  /usr/local/lib/ruby/gems/1.8/gems/actionpack-1.13.3/lib/action_controller/base.rb:708:in `render_with_no_layout'
  /usr/local/lib/ruby/gems/1.8/gems/actionpack-1.13.3/lib/action_controller/layout.rb:256:in `render_without_benchmark'
  /usr/local/lib/ruby/gems/1.8/gems/actionpack-1.13.3/lib/action_controller/benchmarking.rb:50:in `render'
  /usr/local/lib/ruby/1.8/benchmark.rb:293:in `measure'
  /usr/local/lib/ruby/gems/1.8/gems/actionpack-1.13.3/lib/action_controller/benchmarking.rb:50:in `render'
  [RAILS_ROOT]/app/controllers/application.rb:61:in `check_permission'
  /usr/local/lib/ruby/gems/1.8/gems/actionpack-1.13.3/lib/action_controller/filters.rb:456:in `send'
  /usr/local/lib/ruby/gems/1.8/gems/actionpack-1.13.3/lib/action_controller/filters.rb:456:in `call'
  /usr/local/lib/ruby/gems/1.8/gems/actionpack-1.13.3/lib/action_controller/filters.rb:435:in `call'
  /usr/local/lib/ruby/gems/1.8/gems/actionpack-1.13.3/lib/action_controller/filters.rb:637:in `call_filter'
  /usr/local/lib/ruby/gems/1.8/gems/actionpack-1.13.3/lib/action_controller/filters.rb:638:in `call_filter'
  /usr/local/lib/ruby/gems/1.8/gems/actionpack-1.13.3/lib/action_controller/filters.rb:438:in `call'
  /usr/local/lib/ruby/gems/1.8/gems/actionpack-1.13.3/lib/action_controller/filters.rb:637:in `call_filter'
  /usr/local/lib/ruby/gems/1.8/gems/actionpack-1.13.3/lib/action_controller/filters.rb:638:in `call_filter'
  /usr/local/lib/ruby/gems/1.8/gems/actionpack-1.13.3/lib/action_controller/filters.rb:438:in `call'
  /usr/local/lib/ruby/gems/1.8/gems/actionpack-1.13.3/lib/action_controller/filters.rb:637:in `call_filter'
  /usr/local/lib/ruby/gems/1.8/gems/actionpack-1.13.3/lib/action_controller/filters.rb:638:in `call_filter'
  /usr/local/lib/ruby/gems/1.8/gems/actionpack-1.13.3/lib/action_controller/filters.rb:449:in `call'
  /usr/local/lib/ruby/gems/1.8/gems/actionpack-1.13.3/lib/action_controller/filters.rb:637:in `call_filter'
  /usr/local/lib/ruby/gems/1.8/gems/actionpack-1.13.3/lib/action_controller/filters.rb:619:in `perform_action_without_benchmark'
  /usr/local/lib/ruby/gems/1.8/gems/actionpack-1.13.3/lib/action_controller/benchmarking.rb:66:in `perform_action_without_rescue'
  /usr/local/lib/ruby/1.8/benchmark.rb:293:in `measure'
  /usr/local/lib/ruby/gems/1.8/gems/actionpack-1.13.3/lib/action_controller/benchmarking.rb:66:in `perform_action_without_rescue'
  /usr/local/lib/ruby/gems/1.8/gems/actionpack-1.13.3/lib/action_controller/rescue.rb:83:in `perform_action'
  /usr/local/lib/ruby/gems/1.8/gems/actionpack-1.13.3/lib/action_controller/base.rb:430:in `send'
  /usr/local/lib/ruby/gems/1.8/gems/actionpack-1.13.3/lib/action_controller/base.rb:430:in `process_without_filters'
  /usr/local/lib/ruby/gems/1.8/gems/actionpack-1.13.3/lib/action_controller/filters.rb:624:in `process_without_session_management_support'
  /usr/local/lib/ruby/gems/1.8/gems/actionpack-1.13.3/lib/action_controller/session_management.rb:114:in `process'
  /usr/local/lib/ruby/gems/1.8/gems/actionpack-1.13.3/lib/action_controller/base.rb:330:in `process'
  /usr/local/lib/ruby/gems/1.8/gems/rails-1.2.3/lib/dispatcher.rb:41:in `dispatch'
  /usr/local/lib/ruby/gems/1.8/gems/scgi_rails-0.4.3/bin/scgi_service:23:in `process_request'
  /usr/local/lib/ruby/gems/1.8/gems/scgi_rails-0.4.3/bin/scgi_service:21:in `synchronize'
  /usr/local/lib/ruby/gems/1.8/gems/scgi_rails-0.4.3/bin/scgi_service:21:in `process_request'
  /usr/local/lib/ruby/gems/1.8/gems/scgi_rails-0.4.3/lib/scgi.rb:291:in `read_header'
  /usr/local/lib/ruby/gems/1.8/gems/scgi_rails-0.4.3/lib/scgi.rb:253:in `handle_client'
  /usr/local/lib/ruby/gems/1.8/gems/scgi_rails-0.4.3/lib/scgi.rb:234:in `initialize'
  /usr/local/lib/ruby/gems/1.8/gems/scgi_rails-0.4.3/lib/scgi.rb:234:in `new'
  /usr/local/lib/ruby/gems/1.8/gems/scgi_rails-0.4.3/lib/scgi.rb:234:in `handle_client'
  /usr/local/lib/ruby/gems/1.8/gems/scgi_rails-0.4.3/lib/scgi.rb:188:in `listen'
  /usr/local/lib/ruby/gems/1.8/gems/scgi_rails-0.4.3/lib/scgi.rb:186:in `initialize'
  /usr/local/lib/ruby/gems/1.8/gems/scgi_rails-0.4.3/lib/scgi.rb:186:in `new'
  /usr/local/lib/ruby/gems/1.8/gems/scgi_rails-0.4.3/lib/scgi.rb:186:in `listen'
  /usr/local/lib/ruby/gems/1.8/gems/scgi_rails-0.4.3/lib/scgi.rb:412:in `run'
  /usr/local/lib/ruby/gems/1.8/gems/scgi_rails-0.4.3/bin/scgi_service:61