Confirmed that this was happening last night on live as well. My AP pool was continually running dry while I stood in one place attacking nothing, directly after using Supplicate.
Hmm, maybe it's intended? Probably not, but although this is a bug, I still have no problem topping healing done. It's still very annoying at times when you need to keep someone alive though.
Valrith - 40 3x Warrior Priest - Iron Rock Axxen - 2x 2x Chosen - Volkmar
Bump! As a melee WP, AP is EXTREMELY important for my healing and in the thick of combat I rarely finish a supplication cast. (yes that right boys and girls, not all WP's rely solely on our righteous fury).