www.gov.ie

            -be less than 66 characters in length, including the '.ie' characters
-not start with a hyphen '-'
-not have a label ending in a hyphen before the '.ie' e.g. 'xyz-.ie'
-not start with 'xn--' which is reserved for IDN usage, e.g. éire.ie
-not contain any characters outside the range of a-z 0-9 á é í ó ú and - (hyphen)