Map<String,List<String> can't save to mongodb

[wiwi111]

public class UserData{
@id
String id;
public Map < String, List < String >> data=new HashMap < String, ArrayList < String>>();
}

when I save a UserDate to mongodb ,I catched the exception

org.mongodb.morphia.mapping.MappingException: Error mapping field:*******************
at org.mongodb.morphia.mapping.Mapper.toDBObject(Mapper.java:578)
at org.mongodb.morphia.mapping.Mapper.toDBObject(Mapper.java:558)
......
Caused by: java.lang.ClassCastException: java.lang.String cannot be cast to com.mongodb.DBObject
at org.mongodb.morphia.mapping.EmbeddedMapper.writeMap(EmbeddedMapper.java:118)
at org.mongodb.morphia.mapping.EmbeddedMapper.toDBObject(EmbeddedMapper.java:28)
at org.mongodb.morphia.mapping.Mapper.writeMappedField(Mapper.java:668)
at org.mongodb.morphia.mapping.Mapper.toDBObject(Mapper.java:576)
... 29 more

[evanchooly]

Can you please post a test case to the mailing list and we'll try our best to get you sorted out. Thanks.

[evanchooly]

I found the tests that I thought was covering this use case but they were testing something almost the same but not. I have it fixed in master.