No, not in BlockPortal.

Do something like this in this class (you will need to modify this as I'm literally typing it into GitHub):
```java
public static Entity a(World world, int i, double d0, double d1, double d2, org.bukkit.event.entity.CreatureSpawnEvent.SpawnReason reason) {
    // Stuff goes here
    world.addEntity(entity, reason);
    // more stuff after this
}

public static Entity a(World world, int i, double d0, double d1, double d2){
    a(world, i, d0, d1, d2, org.bukkit.event.entity.CreatureSpawnEvent.SpawnReason.SPAWNER_EGG);
}
```

Then in block portal add the `org.bukkit.event.entity.CreatureSpawnEvent.SpawnReason.NETHER_PORTAL` to the method call