Change default date formatter in active admin

In ActiveAdmin dates are printed in the, supposedly American, format %B %d, %Y %H:%M. E.g. March 19, 2013 13:25

However, my "default" frontend prints this using the default Rails (ISO) format, 2013-03-07 14:12:31 UTC, as seen when dropping a <%= Date.new %> anywhere in a view.

1. What is defining the format for the ActiveAdmin dates?
2. Where or how can this be changed, if possible, simply following a global Rails wide i18n setting.