uninitialized constant

Hi, added following line after listening to one of the railscasts on formatting date and time: Time::DATE_FORMATS[:due_time] = "%I:%M %p"

Now i am adding a new column to one of my tables in the database and rails is giving following error: /var/www/html/myapp/pms080204/config/environment.rb:59: uninitialized constant Time::DATE_FORMATS (NameError)

Please help. Thanks.