O'Shea who is from Dublin can play on the wing or up front and is an exciting prospect for club and country. His contract with Birmingham is for two years with the blues having an option of extending it for two more years.
Manager Alex McLeish said on www.elevenaside.com
"James is a quick young winger with good feet. We had him over to take a look at him last season but it was at a stage where we'd already taken on players on loan and we couldn't do a deal.
"He came back on the radar quite recently and he's a good young prospect we hope can be a future star.
"James is not for going into the team right now. We felt he was worth a wee shout because he didn't cost the earth but is hopefully one we can turn into a top player."