On the Check Out page, messages related to the borrower are displayed on the right side. Message text is preceded by a date and library code. The date is displayed in US format (mm/dd/YYY). Is should be displayed formated depending on 'dateformat' syspref.
http://lists.koha-community.org/pipermail/koha-patches/2010-December/013180.html
*** Bug 5476 has been marked as a duplicate of this bug. ***
Pushed to master please test