Start / End Time translation breaks in Ruby 1.9.2

You can't create content in Ruby 1.9.2. The start_time and end_time attribute accessors attempt to parse a hash into a date but this fails in Ruby 1.9.2.

ArgumentError in ContentsController#create

argument out of range
Rails.root: /Users/bamnet/Documents/work/concerto

Application Trace | Framework Trace | Full Trace
app/models/content.rb:51:in end_time=' app/controllers/contents_controller.rb:77:innew'
app/controllers/contents_controller.rb:77:in `create'
Request

Parameters:

{"utf8"=>"✓", "authenticity_token"=>"h7Ea8Z0IvEPedkITESQ1ucXHDAQOiru6Vh3+/+PylXg=", "ticker"=>{"data"=>"This is a test", "name"=>"", "duration"=>"8", "start_time"=>{"date"=>"04/12/2011", "time"=>"12:00 am"}, "end_time"=>{"date"=>"04/20/2011", "time"=>"11:59 pm"}, "user_id"=>"1"}, "type"=>"Ticker", "commit"=>"Create Ticker"}