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 e85fb122..666cdd35 100644
--- a/ethereumj-core/src/main/java/org/ethereum/core/Blockchain.java
+++ b/ethereumj-core/src/main/java/org/ethereum/core/Blockchain.java
@@ -172,7 +172,10 @@ public class Blockchain {
 				logger.debug("Displaying blocks stored in DB sorted on blocknumber");
 				byte[] parentHash = Genesis.PARENT_HASH; // get Genesis block by parentHash
 				for (iterator.seekToFirst(); iterator.hasNext(); iterator.next()) {
-                    this.addBlock(new Block(db.get(parentHash)));
+                    byte[] parentRLP = db.get(parentHash);
+                    if (parentRLP == null) return;
+
+                    this.addBlock(new Block(parentRLP));
                     if (logger.isDebugEnabled())
 						logger.debug("Block: " + getLastBlock().getNumber() + " ---> " + getLastBlock().toFlatString());
 					parentHash = getLastBlock().getHash();
diff --git a/ethereumj-core/src/main/java/org/ethereum/core/Wallet.java b/ethereumj-core/src/main/java/org/ethereum/core/Wallet.java
index ab5261fd..77dff4d1 100644
--- a/ethereumj-core/src/main/java/org/ethereum/core/Wallet.java
+++ b/ethereumj-core/src/main/java/org/ethereum/core/Wallet.java
@@ -105,8 +105,9 @@ public class Wallet {
 
     public void processBlock(Block block){
 
-        // todo: proceed coinbase when you are the miner that gets an award
+        if (block == null) return;
 
+        // todo: proceed coinbase when you are the miner that gets an award
         boolean walletUpdated = false;
 
         List<Transaction> transactions = block.getTransactionsList();