diff --git a/src/main/java/net/minecraft/server/BlockPortal.java b/src/main/java/net/minecraft/server/BlockPortal.java
index 75b833af45..bec5aa8a50 100644
--- a/src/main/java/net/minecraft/server/BlockPortal.java
+++ b/src/main/java/net/minecraft/server/BlockPortal.java
@@ -23,7 +23,8 @@ public class BlockPortal extends BlockHalfTransparent {
             }
 
             if (l > 0 && !world.getType(i, l + 1, k).r()) {
-                Entity entity = ItemMonsterEgg.a(world, 57, (double) i + 0.5D, (double) l + 1.1D, (double) k + 0.5D);
+                // CraftBukkit - set spawn reason to NETHER_PORTAL
+                Entity entity = ItemMonsterEgg.spawnCreature(world, 57, (double) i + 0.5D, (double) l + 1.1D, (double) k + 0.5D, org.bukkit.event.entity.CreatureSpawnEvent.SpawnReason.NETHER_PORTAL);
 
                 if (entity != null) {
                     entity.portalCooldown = entity.ai();
diff --git a/src/main/java/net/minecraft/server/DispenseBehaviorMonsterEgg.java b/src/main/java/net/minecraft/server/DispenseBehaviorMonsterEgg.java
index a854f7ae63..2c14ab03e9 100644
--- a/src/main/java/net/minecraft/server/DispenseBehaviorMonsterEgg.java
+++ b/src/main/java/net/minecraft/server/DispenseBehaviorMonsterEgg.java
@@ -44,7 +44,7 @@ final class DispenseBehaviorMonsterEgg extends DispenseBehaviorItem {
 
         itemstack1 = CraftItemStack.asNMSCopy(event.getItem());
 
-        Entity entity = ItemMonsterEgg.a(isourceblock.k(), itemstack.getData(), event.getVelocity().getX(), event.getVelocity().getY(), event.getVelocity().getZ());
+        Entity entity = ItemMonsterEgg.spawnCreature(isourceblock.k(), itemstack.getData(), event.getVelocity().getX(), event.getVelocity().getY(), event.getVelocity().getZ(), org.bukkit.event.entity.CreatureSpawnEvent.SpawnReason.DISPENSE_EGG);
 
         if (entity instanceof EntityLiving && itemstack.hasName()) {
             ((EntityInsentient) entity).setCustomName(itemstack.getName());
diff --git a/src/main/java/net/minecraft/server/ItemMonsterEgg.java b/src/main/java/net/minecraft/server/ItemMonsterEgg.java
index 34c21efc5e..a41184ea6a 100644
--- a/src/main/java/net/minecraft/server/ItemMonsterEgg.java
+++ b/src/main/java/net/minecraft/server/ItemMonsterEgg.java
@@ -92,6 +92,12 @@ public class ItemMonsterEgg extends Item {
     }
 
     public static Entity a(World world, int i, double d0, double d1, double d2) {
+        // CraftBukkit start - delegate to spawnCreature
+        return spawnCreature(world, i, d0, d1, d2, org.bukkit.event.entity.CreatureSpawnEvent.SpawnReason.SPAWNER_EGG);
+    }
+
+    public static Entity spawnCreature(World world, int i, double d0, double d1, double d2, org.bukkit.event.entity.CreatureSpawnEvent.SpawnReason spawnReason) {
+        // CraftBukkit end
         if (!EntityTypes.a.containsKey(Integer.valueOf(i))) {
             return null;
         } else {
@@ -106,7 +112,7 @@ public class ItemMonsterEgg extends Item {
                     entityinsentient.aP = entityinsentient.yaw;
                     entityinsentient.aN = entityinsentient.yaw;
                     entityinsentient.a((GroupDataEntity) null);
-                    world.addEntity(entity, org.bukkit.event.entity.CreatureSpawnEvent.SpawnReason.SPAWNER_EGG); // CraftBukkit
+                    world.addEntity(entity, spawnReason); // CraftBukkit
                     entityinsentient.r();
                 }
             }