diff --git a/ethereumj-core/src/main/java/org/ethereum/core/Blockchain.java b/ethereumj-core/src/main/java/org/ethereum/core/Blockchain.java
index 34a532e0..4dcb8e25 100644
--- a/ethereumj-core/src/main/java/org/ethereum/core/Blockchain.java
+++ b/ethereumj-core/src/main/java/org/ethereum/core/Blockchain.java
@@ -147,6 +147,20 @@ public class Blockchain {
         if (listener != null)
             listener.trace(String.format("Block chain size: [ %d ]", this.getSize()));
 
+        EthereumListener ethereumListener =  WorldManager.getInstance().getListener();
+        if (ethereumListener != null)
+            ethereumListener.onBlock(block);
+
+/*
+        if (lastBlock.getNumber() >= 30) {
+            System.out.println("** checkpoint **");
+
+            this.close();
+            WorldManager.getInstance().getRepository().close();
+            System.exit(1);
+        }
+*/
+
     }
     
     public void processBlock(Block block) {
diff --git a/ethereumj-core/src/main/java/org/ethereum/listener/EthereumListener.java b/ethereumj-core/src/main/java/org/ethereum/listener/EthereumListener.java
index 0a0d3543..51f14985 100644
--- a/ethereumj-core/src/main/java/org/ethereum/listener/EthereumListener.java
+++ b/ethereumj-core/src/main/java/org/ethereum/listener/EthereumListener.java
@@ -1,5 +1,7 @@
 package org.ethereum.listener;
 
+import org.ethereum.core.Block;
+
 /**
  * www.ethereumJ.com
  *
@@ -10,4 +12,5 @@ package org.ethereum.listener;
 public interface EthereumListener {
 
     public void trace(String output);
+    public void onBlock(Block block);
 }
diff --git a/ethereumj-core/src/main/java/org/ethereum/net/client/EthereumProtocolHandler.java b/ethereumj-core/src/main/java/org/ethereum/net/client/EthereumProtocolHandler.java
index 50431bc3..682477c3 100644
--- a/ethereumj-core/src/main/java/org/ethereum/net/client/EthereumProtocolHandler.java
+++ b/ethereumj-core/src/main/java/org/ethereum/net/client/EthereumProtocolHandler.java
@@ -66,6 +66,7 @@ public class EthereumProtocolHandler extends ChannelInboundHandlerAdapter {
 
         logger.info("Send: " + StaticMessages.HELLO_MESSAGE.toString());
         msgQueue.sendMessage(StaticMessages.HELLO_MESSAGE);
+        sendPing();
 
         // sample for pinging in background
         timer.scheduleAtFixedRate(new TimerTask() {
@@ -249,6 +250,8 @@ public class EthereumProtocolHandler extends ChannelInboundHandlerAdapter {
             RLPList rlpList = RLP.decode2(payload);
             GetChainMessage getChainMessage = new GetChainMessage(rlpList);
 
+
+
             logger.info(getChainMessage.toString());
             if (peerListener != null) peerListener.console(getChainMessage.toString());
         }
@@ -323,6 +326,7 @@ public class EthereumProtocolHandler extends ChannelInboundHandlerAdapter {
                 SystemProperties.CONFIG.maxBlocksQueued()) return;
 
         Block lastBlock = WorldManager.getInstance().getBlockchain().getBlockQueue().getLast();
+        if (lastBlock == null) return;
 
         byte[] hash = lastBlock.getHash();
         GetChainMessage chainMessage =