Moved CraftVehicle.*Velocity() to CraftEntity as velocity is a component of all entities.

src/main/java/org/bukkit/craftbukkit/CraftEntity.java

@@ -4,6 +4,7 @@ package org.bukkit.craftbukkit;
 import net.minecraft.server.Entity;
 import net.minecraft.server.WorldServer;
 import org.bukkit.Location;
+import org.bukkit.Vector;
 import org.bukkit.World;
 
 public abstract class CraftEntity implements org.bukkit.Entity {
@@ -19,6 +20,16 @@ public abstract class CraftEntity implements org.bukkit.Entity {
         return new Location(getWorld(), entity.p, entity.q, entity.r, entity.v, entity.w);
     }
 
+    public Vector getVelocity() {
+        return new Vector(entity.s, entity.t, entity.u);
+    }
+
+    public void setVelocity(Vector vel) {
+        entity.s = vel.getX();
+        entity.t = vel.getY();
+        entity.u = vel.getZ();
+    }
+
     public World getWorld() {
         return ((WorldServer)entity.l).getWorld();
     }

src/main/java/org/bukkit/craftbukkit/CraftVehicle.java

@@ -10,11 +10,8 @@ import org.bukkit.Vehicle;
  * @author sk89q
  */
 public abstract class CraftVehicle extends CraftEntity implements Vehicle {
-    private net.minecraft.server.Entity vehicle;
-    
     public CraftVehicle(CraftServer server, net.minecraft.server.Entity entity) {
         super(server, entity);
-        vehicle = entity;
     }
 
     public Entity getPassenger() {
@@ -24,14 +21,4 @@ public abstract class CraftVehicle extends CraftEntity implements Vehicle {
     public boolean isEmpty() {
         return getHandle().j == null;
     }
-
-    public Vector getVelocity() {
-        return new Vector(vehicle.s, vehicle.t, vehicle.u);
-    }
-
-    public void setVelocity(Vector vel) {
-        vehicle.s = vel.getX();
-        vehicle.t = vel.getY();
-        vehicle.u = vel.getZ();
-    }
 }