VALUED ORDER BY is not working in CBAS.

Executed query:
SELECT feature_name FROM default_shadow WHERE coverage_tests.P0 IS VALUED ORDER BY feature_name;

Exception raised:
CBQError: CBQError: host 172.23.108.231: ERROR:{u'status': u'fatal', u'errors': [

{u'msg': u'Syntax error: In line 1 >>SELECT feature_name FROM default_shadow WHERE coverage_tests.P0 IS VALUED ORDER BY feature_name;;<< Encountered <IDENTIFIER> "VALUED" at column 68. ', u'code': u'1'}

], u'metrics':

{u'elapsedTime': u'44.495877ms', u'executionTime': u'25.040814ms', u'resultSize': 0, u'resultCount': 0}

, u'requestID': u'750a17ff-2f86-4430-bace-48d58ec0d7c0', u'clientContextID': u'null', u'signature': u'*'}