Rails 3.2.3

In production mode I have an error and it displays standard "we're sorry" page. In development mode there is no error.

I need to get more information about the error so I want to turn off "we're sorry" page and see the error. I know it has to be lauched as "rails s -e production" and I do it at my local computer. But how can turn off "we're sorry" page?