--- a/net/minecraft/server/BlockTrapdoor.java
+++ b/net/minecraft/server/BlockTrapdoor.java
@@ -2,6 +2,8 @@
 
 import com.google.common.base.Predicate;
 
+import org.bukkit.event.block.BlockRedstoneEvent; // CraftBukkit
+
 public class BlockTrapdoor extends Block {
 
     public static final BlockStateDirection FACING = BlockStateDirection.of("facing", (Predicate) EnumDirection.EnumDirectionLimit.HORIZONTAL);
@@ -101,6 +103,19 @@
                 boolean flag = world.isBlockIndirectlyPowered(blockposition);
 
                 if (flag || block.isPowerSource()) {
+                    // CraftBukkit start
+                    org.bukkit.World bworld = world.getWorld();
+                    org.bukkit.block.Block bblock = bworld.getBlockAt(blockposition.getX(), blockposition.getY(), blockposition.getZ());
+
+                    int power = bblock.getBlockPower();
+                    int oldPower = (Boolean) iblockdata.get(OPEN) ? 15 : 0;
+
+                    if (oldPower == 0 ^ power == 0 || block.isPowerSource()) {
+                        BlockRedstoneEvent eventRedstone = new BlockRedstoneEvent(bblock, oldPower, power);
+                        world.getServer().getPluginManager().callEvent(eventRedstone);
+                        flag = eventRedstone.getNewCurrent() > 0;
+                    }
+                    // CraftBukkit end
                     boolean flag1 = ((Boolean) iblockdata.get(BlockTrapdoor.OPEN)).booleanValue();
 
                     if (flag1 != flag) {