I'm not sure. I never checked the functionality in the past to know that it worked then.
My click to cure on my group/player window have canceled casting to cure since the beginning, but i've had a few request to change it, since it was dangerous for a healer to cancel a heal
I guess we'll have to get some Dev insight on this one? I don't really see how queuing an ability can be bad, since you can only queue 1. /shrug