Boats multiplayer duplication and HUD issue

On the server I play on players will be kicked for flying, often while riding a boat in this world I will get falsely kicked for flying. Also, this server also has a world limit set so when I ride a boat past that world limit I get kicked for flying. Now the real issue is that when I'm riding a boat and I get kicked, in a fashion like that or otherwise, when I re- log I am set where I was kicked from but my boat duplicates itself multiple times and most of the boats break. With the F3 menu up I saw that when this happened my entity count reached about 5000. I haven't tested this in single player, and the server I play on is bukkit (so not sure if it's just an issue with bukkit servers). Also, as a side note, I've noticed that while I'm riding in a boat my hunger bar does not show (but I can still eat) and also the hitbox of the boat often separates from the boat itself upon dismounting the boat, causing me to have to re-log to be able to re-enter a boat.