Thread:Project:Support desk/How to change format of lastmod's date/time

How can you change the date/time format of last mod?

Eg, changing "This page was last modified on 20 March 2014, at 16:00." to "This page was last modified on March 20, 2014, at 4:00PM."

Edit: Date can be set at preferences, but is there something for time format?