untested, see blog post http://noisycode.com/blog/2014/07/27/akka-and-jdbc-to-services/

gistfile1.scala

val pool = new BoneCP(config)

val getConn = () => pool.getConnection()
val relConn = (c: Connection) => pool.releaseConnection(c)

class MyActor(get: () => Connection, rel: (c: Connection) => Unit) extends Actor {
  lazy val c = get()
  
  override def preRestart(why: Throwable, msg: Option[Any]): Unit = {
    rel(c)
  }

  def receive = ...
}