@LeandroGuillen , regarding "The response of a DELETE is not valid JSON" , note there is not only one DELETE operation. In fact, there are 3 ones:

1. DELETE /ngsi10/contextEntities/{EntityID} (the one referred by #225)
2. DELETE /ngsi10/contextEntities/{EntityID}/attributes
3. DELETE /ngsi10/contextEntities/{EntityID}/attributes/{attributeName}/{valueID} 

Does the problem with JSON response happens in all three or only number 1?