The Collaborative International Dictionary of English v.0.48:

Undeceived \Undeceived\
   See deceived.

WordNet (r) 3.0 (2006):

undeceived
    adj 1: freed of a mistaken or misguided notion; "some people are
           still not disabused of the old idea that the universe
           revolves around the Earth" [syn: disabused(p),
           undeceived]

Moby Thesaurus II by Grady Ward, 1.0:

35 Moby Thesaurus words for "undeceived":
   alive to, appreciative of, apprised of, awake to, aware of,
   behind the curtain, behind the scenes, blase, cognizant of,
   conscious of, disabused, disappointed, disenchanted, disillusioned,
   enlightened, hep to, in the know, in the secret, informed of,
   let into, mindful of, no stranger to, on to, privy to,
   put straight, robbed of illusion, seized of, sensible of,
   sensible to, set right, sophisticated, streetwise, uncharmed,
   unspelled, wise to