Restlet Android & GAE, three methods works one doesnt

[JuanMa via StackOverflow]

i am trying to figure out why my code is returning null in some place of my code and why it is working well in another one.

My working code is:

ClientResource cr = new ClientResource(TipificacionRestLetInterface.URL);
TipificacionRestLetInterface resource = cr.wrap(TipificacionRestLetInterface.class);
ArrayList<AreaDTO> areas = resource.getAreas();

My not working code is:

ClientResource cr = new ClientResource(InspeccionRestLetInterface.URL);
cr.setRequestEntityBuffering(true);
InspeccionRestLetInterface resource = cr.wrap(InspeccionRestLetInterface.class);
result = resource.getDTOByQuery(filter);

Like you can see both code's are practically the same but the first return a arraylist with objects and de last one null although my server side code return a arraylist with objects.

I don't understand what is happening and I banging my head against the wall.

My restlet interfaces:

public interface TipificacionRestLetInterface {
.....
@Get
public ArrayList<AreaDTO> getAreas();
.....}

public interface InspeccionRestLetInterface {
.....
@Post
public ArrayList<InspeccionDTO> getDTOByQuery(InspeccionFilterDTO filter);
......}

Any ideas ?

** EDIT **

I was searching and testing a little more. I guess I found the problem, when my client calls a method passing params and getting a result it get lock somewhere in the restlet library.

I did the following tests:

No params No result, its OK:

void getlist();

Params and No result, it's OK

void getList(InspeccionFilterDTO filter);

No params, and a result, it's OK:

ArrayList<InspeccionDTO> getList();

Params and a Result, it's NOT OK

ArrayList<InspeccionDTO> getList(InspeccionFilterDTO filter);

Maybe is it a bug or a restriction?

** EDIT END **

Thanks in advance JM

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