Forum: Typo 5.0.3 error: NoMethodError in ArticlesController#index

I recently used svn to update to Typo 5.0.3. After the update I'm
getting a 500 Server Error when trying to go to the home page of my
blog (http://blog.peekle.net), even though I can use the admin just
fine. I ran under WEBrick and got the error in the subject line.
Further info (a capture from Lynx):

                                  Action Controller: Exception caught 
(p1 of 8)

                   NoMethodError in ArticlesController#index

You have a nil object when you didn't expect it!
The error occurred while evaluating nil.lang

   RAILS_ROOT: /home/xxxx/typo

   Application Trace | Framework Trace | Full Trace
app/controllers/application.rb:46:in `load_lang'

vendor/rails/actionpack/lib/action_controller/filters.rb:469:in `send!'
vendor/rails/actionpack/lib/action_controller/filters.rb:469:in `call'
vendor/rails/actionpack/lib/action_controller/filters.rb:441:in `run'
vendor/rails/actionpack/lib/action_controller/filters.rb:718:in 
`run_before_fil
ters'
vendor/rails/actionpack/lib/action_controller/filters.rb:697:in 
`call_filters'
vendor/rails/actionpack/lib/action_controller/filters.rb:691:in 
`perform_action
_without_benchmark'
vendor/rails/actionpack/lib/action_controller/benchmarking.rb:68:in 
`perform_ac
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Anyone know what's going on here? I'm stumped.