The University of California Press has just published Floyd Levin's
book "Classic Jazz - A Personal View Of The Music And The Musicians,"
which mentions the De Forest Phonofilm talking movie:

  "Al Jolson's 1927 film The Jazz Singer is usually identified as the
   first American motion picture to include sound; the first talking
   movie actually appeared four years earlier.  It was advertised as
   a "De Forest Phonofilm -- it actually talks and reproduces music
   without use of a phonograph."  Sissle and Blake were the only black
   performers in the stellar vaudeville cast, which also included Weber
   and Fields, Eddie Cantor, and Phil Baker.  The film premiered at the
   Rivoli Theater in New York City in April 1923, making Sissle and
   Blake the first black performers to appear in a "talkie."  Blake
   made several more film appearances over the years.  His last was in
   "Scott Joplin", starring Billy Dee Williams, in 1976 -- fifty-three
   years after his screen debut."

The entire article about Eubie Blake is posted at
http://www.ucpress.edu/books/pages/8735.html

Robbie Rhodes