WIth the addition of the custom loot tables for mobs, the Enderman doesn't drop the item they hold anymore. The Enderman was holding a grass block but when he died, he drop an enderpearl but NOT a grass block when he should.
Zombies also doesn't seem to drop the item they had in there hand even if it's an item thrown at them. After killing about 300+ zombies, no rare drops occured, not one ingot/armor/sword/carrot/potato, just rotton flesh.
Can confirm that mobs don't drop their equipment, but rare drop are working fine : keep in mind that the player must kill the zombies to have a chance of getting a rare drop, /kill or other indirect damages(tnt, lava, fall damage) won't work.