Re: UK visa needed (PM Friday, 24 January 2014) – The Irish Minister for Justice and Equality Alan Shatter announced that from 18 November 2013, citizens of Thailand will be able to avail of the Irish short stay visa waiver programme. This will allow visitors from Thailand who have lawfully entered the UK (including Northern Ireland) on a valid UK visa, to travel to Ireland without the requirement to obtain an Irish visa, and without any additional paperwork or fees.
I think that should clear up the obvious confusion created by the original article in the Pattaya Mail.
Thai people will not be able to go to S Ireland without a visa and subsequently travel to the UK without a valid UK visa. Even now, if you take a ferry from Ireland to the UK you need to show your ID that shows you are eligible for entry to the UK before you board the ferry.