Seapoint play in Division 2A of the Ulster Bank League and have a strong tradition in developing young players.
Recent Seapoint players who have progressed to professional ranks include Felix Jones (Munster), Aaron Dundon (Leinster) and Mick Noone (Leicester) while this year's 20 year-old out-half Peter Lydon has recently been offered a contract with Stade Francais.
Director of rugby at Seapoint, Bob Nutty, said: "We are delighted that Eric is becoming our head coach. He has extensive knowledge and experience as a player and coach and has a proven record in developing young players. He will be a big asset to our club."
Miller himself commented: "Seapoint has a tradition of being one of the strongest community-based clubs in Leinster while also creating a unique atmosphere for players.
"They are a very progressive club and I look forward to working with the coaches, players and officials in bringing further success on the field."
Eric will also continue with his role as Head Coach for the Terenure based junior rugby club, CYM RFC, for the coming season.