I found that by changing some simple DNS Settings in the WiFi settings on the iPad I could access US Netflix which has far more content than Irish Netflix.
Do this by going into WiFi settings and selecting Static.
When configured correctly it should look like this:
Primary DNS Server: 220.127.116.11
Secondary DNS Server: 18.104.22.168
A similar technique can be used to get US Netflix to work on Sony PS3, Google Nexus 7, Smartphones and computers.
Note: This can make websites and apps think you are in America which may have an adverse (or positive) effect on your other iPad apps, so you may wish to change these settings back when not using Netflix.