If the Date field is set to 1970-01-01 in UTC, the REST API gives null as its fieldValue instead of

Steps to reproduce (setting 1970-01-01UTC might be tricky, the easiest way I found was to update directly data_int column in ezcontentobject_attribute)

1. create a Content Type with a Date field definition
2. create a Content and set the Date to 1970-01-01
3. Load the Content in the REST API, the fieldValue is null