The Collaborative International Dictionary of English v.0.48:

Inspirational \In`spi*ra"tion*al\, a.
   1. Pertaining to inspiration.
      [1913 Webster]

   2. Imparting inspiration[2]; as, an inspirational sermon.
      [PJC]

WordNet (r) 3.0 (2006):

inspirational
    adj 1: imparting a divine influence on the mind and soul