[Android] Custom User class

I just created a custom user class that extends the BackendlessUser. It look like this:

public class User extends BackendlessUser{



public void setLastName(String lastName) {
 setProperty("lastName", lastName);
}
public String getLastName() {
 return (String) getProperty("lastName");
}
}

I registered the class with:

Backendless.Data.mapTableToClass("Users", User.class);

So far so good, but if i try to query for a User with:

Backendless.Persistence.of(User.class).find(someQuery);

The query returns the desired number of results, but every property in every object is null.
objectId, email, lastName… everything is null.
How can this be and how can i solve this? Thanks!

Hi Florian!
Answer is already here:

http://support.backendless.com/t/how-to-create-custom-backendlessuser-objects
Hope this helps.

I already read this answer and did everything it says.

I still get an empty properties map for every userobject.

Can you show what your code looks like now after you made the changes?