Djinni Blood is currently not dropping off the trash on island 4 while sources indicate that it should be. I cannot give an exact sample size of how many horses I have killed to test this, but I can say that I have pretty much killed some amount of trash from that island every single day since the zone was released.
Source:
http://eq.magelo.com/item/20784
This item is currently used to complete the necromancer test of the mind.
Source:
http://everquest.allakhazam.com/db/quest.html?quest=349