Surrounds Placement for Diffused Sound?

Need opinions and advise for the following surrounds and back speakers placement. I have the following theater room configuration: Theater Room (21.5' L X 15.5 W X 8.5 H) L C R S-1L S-1R S-2L S-2R R-L R-R Speakers: Paradigm Reference 40s, CC, AMS450, ADP Processor: Lexicon MC-1 Amps: Bryston 4BST for L & R, 3BST (bridged) for CC, and 8BST for Sides and Rears Notice that I have 2 pairs of side speakers on the ceiling... The reason I'm going this route is because the Paradigm ADPs (dipoles) cannot be mounted on the ceiling. So in order to emulate the dipole effect, I am thinking in installing on the ceiling an array of the Paradigms in-walls (AMS 450s) on each side, pretty much firing down on each row of seats (2). One side of the wall in the room is glass. The Rear speakers are the Dipoles ADPs, each shooting to each side of the wall. Any advise on this set up? Would the 4 sides on the ceiling give me the same effect as having a pair of dipoles on each side? Any conflict between the direct and dipoles in the back? GB
You'd be better off with the dipoles on the sides of the ceiling and the directionals in the back, if at all possible. Ideally, you want same tweeter and woofer configuration for proper timbre match. If memory serves correct, dipole surrounds have woofers out of phase with each other and the tweeters both in phase. You could probably accomodate this yourself.
By the way, nice room dimensions, should work well. FYI, have pair of Triad Silver THX OnWall surrounds listed!