Minecraft wiki entry for Development_versions, associated text: MC-133 – Mobs walking slow when the player hits them.
MC-4024 – Chest glitch; server/client desyncronization.
MC-4528 – Flaming arrows take a few seconds to visibly catch fire.
MC-4634 – Cannot remove XP bars using the /xp -1L command when between levels 0 and 1.