Completely let this one slip. The answer is Robert Joy who plays Dr. Sid Hammerback.
Robert Joy was born in St John's Newfoundland (though IMDB says Montreal). He attended Memorial University of Newfoundland and Corpus Christi College at Oxford, where he was a Rhodes Scholar. He was a member of the Newfoundland based comedy troupe CODCO, and participated in some episodes of their TV series in the late 1980s and early '90s. His first TV acting credit was a minor role in the epic Canadian mini-series The National Dream. He played Harry K. Thaw, the man who shot Stanford White and was married to Evelyn Nesbitt (Elizabeth McGovern) in the movie Ragtime. Though primarily based in the United States he still works in Canada occasionally.
While A.J. Buckley who plays Adam is a Canadian citizen, he was born in Ireland and immigrated to British Columbia with his parents when he was 6 years old.
Like I said, We Canucks are everywhere!