The Collaborative International Dictionary of English v.0.48:

Unsatisfactory \Unsatisfactory\
   See satisfactory.

WordNet (r) 3.0 (2006):

unsatisfactory
    adj 1: not giving satisfaction; "shops should take back
           unsatisfactory goods"; "her performance proved to be
           unsatisfactory"; "life is becoming increasingly
           unsatifactory"; "our discussion was very unsatisfactory"
           [ant: satisfactory]

Moby Thesaurus II by Grady Ward, 1.0:

46 Moby Thesaurus words for "unsatisfactory":
   amiss, bad, bum, crappy, defective, deficient, disappointing,
   disheartening, displeasing, dissatisfactory, failing,
   falling short, faulty, flawed, found wanting, imperfect,
   inadequate, inappropriate, incommensurate, incompetent, incomplete,
   inferior, insufficient, lacking, not enough, not good enough, poor,
   punk, rotten, second best, tantalizing, teasing, too little,
   unacceptable, unequal to, unfulfilling, ungratifying, unqualified,
   unsatisfying, unsufficing, unsuitable, unworthy, up, wanting, weak,
   wrong