No doubt that claim may leave some US visitors scratching their heads and wondering what the Irish airport has against the patron saint who will be celebrated around the world on 17 March.And they will soon set them right.In a message posted on Facebook, Dublin Airport vehemently declared that it is St Patrick's Day, Patrick's Day, St Paddy's Day or Paddy's Day."It is not St Patty's Day or Patty's Day. Not this year, not last year. Not ever," they added firmly.And it seems they're not the only ones with that gripe.The poster bearing the message has racked up more than 5,000 'likes' on Facebook and been shared more than 8,000 times.It has also prompted nearly 250 responses.While some people commented that it wasn't a big deal or suggested the Patty rightly came from the 'T' in Patrick, others shared the airport's sentiments.Amid the debate, Dublin Airport reiterated its point."Whether in Missouri, Montreal, Moscow or Mullingar, it's Paddy not Patty," one comment insisted.Another added, in response to a suggestion that it was an easy mistake: "Ah, don't be going soft on us now. A small child can be taught the difference between Paddy and Patty."A message delivered all in good humour, no doubt - just don't risk their wrath by wishing them a Happy St Patty's Day!