I've created a custom package that has the patch applied. It's in my PPA (Personal Package Archive).
To fix am/pm for the irish locale, you'll need to add my PPA to your apt sources list. Download this file http://technomancy.org/ubuntu/rorymcc-ppa.list into /etc/apt/sources.list.d/,
eg use the following command
Then just update your software and you should have the proper time format available. To check from the command line, enter
sudo wget -O /etc/apt/source.list.d/rorymcc-ppa.list http://technomancy.org/ubuntu/rorymcc-ppa.list
, it'll give the time. If it has an AM or PM, it has worked.
LANG=en_IE.UTF-8 date '+%r'
This also enables the 12 hour clock on the clock applet.