json4s not serializing/deserializing nested List[Int]

   import org.json4s.native.JsonMethods._
   import org.json4s.DefaultFormats

    implicit val formats = DefaultFormats ++ org.json4s.ext.JodaTimeSerializers.all

    case class SimpleDomainClass1(simpleList: List[Int], simpleNestedClass: SimpleDomainClass2)
    case class SimpleDomainClass2(simpleBool: Boolean, simpleString: String, simpleInt: Int)

    val domain1 = SimpleDomainClass1(List(1, 2, 3), SimpleDomainClass2(true, "xpto", 11))

    val json = parse("""
        {"simpleList":[1, 2], "simpleNestedClass":{"simpleBool":true,"simpleString":"lol","simpleInt":1}}
      """)

    val obj = json.extract[SimpleDomainClass1]
    /* Can't find constructor for SimpleDomainClass1
    org.json4s.package$MappingException: Can't find constructor for SimpleDomainClass1
    at org.json4s.reflect.ScalaSigReader$.readConstructor(ScalaSigReader.scala:27)
    ...
    */