Fixed exploit with Ender Pearls, and made them perform a damage event. This fixes BUKKIT-38

src/main/java/net/minecraft/server/EntityEnderPearl.java

@@ -0,0 +1,52 @@
+package net.minecraft.server;
+
+import org.bukkit.Bukkit;
+import org.bukkit.craftbukkit.entity.CraftPlayer;
+import org.bukkit.event.entity.EntityDamageEvent;
+
+public class EntityEnderPearl extends EntityProjectile {
+    public EntityEnderPearl(World world) {
+        super(world);
+    }
+
+    public EntityEnderPearl(World world, EntityLiving entityliving) {
+        super(world, entityliving);
+    }
+
+    public EntityEnderPearl(World world, double d0, double d1, double d2) {
+        super(world, d0, d1, d2);
+    }
+
+    protected void a(MovingObjectPosition movingobjectposition) {
+        if (movingobjectposition.entity != null && movingobjectposition.entity.damageEntity(DamageSource.projectile(this, this.shooter), 0)) {
+            ;
+        }
+
+        for (int i = 0; i < 32; ++i) {
+            this.world.a("portal", this.locX, this.locY + this.random.nextDouble() * 2.0D, this.locZ, this.random.nextGaussian(), 0.0D, this.random.nextGaussian());
+        }
+
+        if (!this.world.isStatic) {
+            // CraftBukkit start - dupe fix + damage event
+            boolean damage = false;
+            if (this.shooter != null) {
+                if (this.shooter instanceof EntityPlayer) {
+                    damage = ((CraftPlayer)this.shooter.bukkitEntity).isOnline();
+                } else {
+                    damage = true;
+                }
+            }
+
+            if (damage) {
+                this.shooter.a_(this.locX, this.locY, this.locZ);
+                this.shooter.fallDistance = 0.0F;
+                EntityDamageEvent event = new EntityDamageEvent(getBukkitEntity(), EntityDamageEvent.DamageCause.FALL, 5);
+                Bukkit.getPluginManager().callEvent(event);
+                this.shooter.damageEntity(DamageSource.FALL, event.getDamage());
+            }
+            // CraftBukkit end
+
+            this.die();
+        }
+    }
+}