Jackson deserialization of interface affects constituent member's deserializaton - jackson

Question

I have an interface type with many implementation classes. I can serialize/deserialize this either by
#JsonDeserialize(using = AlarmStateDeserializer.class)
#JsonSerialize(using = AlarmStateSerializer.class)
#JsonTypeInfo( use = JsonTypeInfo.Id.NONE)
public interface AlarmState
{
:
or
#JsonTypeInfo(use = JsonTypeInfo.Id.NAME, include = JsonTypeInfo.As.EXISTING_PROPERTY, property = "type")
#JsonSubTypes({
#JsonSubTypes.Type(value = AcknowledgedState.class, name = "acknowledged"),
#JsonSubTypes.Type(value = ActivatedState.class, name = "activated"),
#JsonSubTypes.Type(value = DeactivatedState.class, name = "deactivated"),
#JsonSubTypes.Type(value = BlockedState.class, name = "blocked"),
#JsonSubTypes.Type(value = ReactivatedState.class, name = "reactivated"),
#JsonSubTypes.Type(value = DisabledState.class, name = "disabled"),
#JsonSubTypes.Type(value = NormalState.class, name = "normal"),
})
and that works fine when I seralize/deserialize the AlarmState directly in the ObjectMapper.
BUT, if I include the AlarmState as a property in another type, it insists to have a type for that field.
I have tried just about every other way I can think of, but for instance;
#JsonTypeInfo( use = JsonTypeInfo.Id.NONE )
#JsonDeserialize(as = AlarmImpl.class)
public interface Alarm
{
AlarmState getState();
:
(It doesn't matter if I deserialize the AlarmImpl directly either, same result)
And I will get the following exception;
Could not resolve subtype of [simple type, class com.sensetif.pipes.alarms.AlarmState]: missing type id property 'type' (for POJO property 'state')
I have also tried to put all kinds of annotations on the getState() method, but to no prevail.
FTR; the json in question is;
{
"labels": [],
"state": {
"name": "normal",
"description": "Normal state indicates everything is fine.",
"creationTime": "1970-01-01T00:00:00Z"
},
"counter": 0,
"name": "niclas1",
"description": null,
"condition": false,
"alarmClass": "C",
"organization": 0,
"parameters": null
}
How can it be that the underlying type deserializes fine, but not when it is part of an outer object??