var data = JSON.stringify({
  "user":  "/api/v1/user/1",
  "title": "My New Blog Post",
  "body": "Something interesting should be here..."
});

$.ajax({
  url:          '/api/v1/entry/',
  type:         'POST',
  contentType:  'application/json',
  data:         data,
  dataType:     'json',
  processData:  false
})