To the best of my knowledge this was published in 2007 and is the most up to date version available and does contain provisions for the prosecution of a person engaging with a person under the age of 18
Head 5: Soliciting or paying for purpose of sexually exploiting a child
(5) A person guilty of an offence under this head is liable on conviction on
indictment -
(b) in case the child was 15 years of age or over but under 18
years of age, to imprisonment for a term not exceeding 3
years.
http://www.justice.ie/en/JELR/Crimin...king%20pdf.pdf