diff --git a/ethereumj-core/src/main/java/org/ethereum/core/Block.java b/ethereumj-core/src/main/java/org/ethereum/core/Block.java
index f8ce6771..d1fd49f7 100644
--- a/ethereumj-core/src/main/java/org/ethereum/core/Block.java
+++ b/ethereumj-core/src/main/java/org/ethereum/core/Block.java
@@ -66,9 +66,6 @@ public class Block {
         this.parsed = true;
     }
 
-	// [parent_hash, uncles_hash, coinbase, state_root, tx_trie_root,
-	// difficulty, number, minGasPrice, gasLimit, gasUsed, timestamp,  
-	// extradata, nonce]
     private void parseRLP() {
 
         RLPList params = (RLPList) RLP.decode2(rlpEncoded);
@@ -294,15 +291,15 @@ public class Block {
 	 * likely next period. Conversely, if the period is too large, the difficulty, 
 	 * and expected time to the next block, is reduced.
 	 */
-    private boolean isValid() {
-    	boolean isValid = false;
+    public boolean isValid() {
+    	boolean isValid = true;
     	
     	// verify difficulty meets requirements
-    	isValid = this.getDifficulty() == this.calcDifficulty();
+    	//isValid = this.getDifficulty() == this.calcDifficulty();
     	// verify gasLimit meets requirements
-    	isValid = this.getGasLimit() == this.calcGasLimit();
+    	//isValid = this.getGasLimit() == this.calcGasLimit();
     	// verify timestamp meets requirements
-    	isValid = this.getTimestamp() > this.getParent().getTimestamp();
+//    	isValid = this.getTimestamp() > this.getParent().getTimestamp();
     	
     	return isValid;
     }
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 2c08d939..b4ef3687 100644
--- a/ethereumj-core/src/main/java/org/ethereum/core/Blockchain.java
+++ b/ethereumj-core/src/main/java/org/ethereum/core/Blockchain.java
@@ -83,11 +83,13 @@ public class Blockchain extends ArrayList<Block> {
     }
     
     private void addBlock(Block block) {
-		this.wallet.processBlock(block);
-        this.gasPrice = block.getMinGasPrice();
-		if(lastBlock == null || block.getNumber() > lastBlock.getNumber())
-			this.lastBlock = block;
-		this.add(block);
+    	if(block.isValid()) {
+			this.wallet.processBlock(block);
+	        this.gasPrice = block.getMinGasPrice();
+			if(lastBlock == null || block.getNumber() > lastBlock.getNumber())
+				this.lastBlock = block;
+			this.add(block);
+    	}
     }
     
     public long getGasPrice() {
diff --git a/ethereumj-core/src/main/java/org/ethereum/core/Denomination.java b/ethereumj-core/src/main/java/org/ethereum/core/Denomination.java
index 8e2b6b97..2d5fa7c3 100644
--- a/ethereumj-core/src/main/java/org/ethereum/core/Denomination.java
+++ b/ethereumj-core/src/main/java/org/ethereum/core/Denomination.java
@@ -10,15 +10,17 @@ public enum Denomination {
 	SHANNON(newBigInt(9)),
 	SZABO(newBigInt(12)),
 	FINNY(newBigInt(15)),
-	ETHER(newBigInt(18));
-	
+	ETHER(newBigInt(18)),
+	EINSTEIN(newBigInt(21)),
+	DOUGLAS(newBigInt(42));					 
+			 
 	private BigInteger amount;
 	
 	private Denomination(BigInteger value) {
 		this.amount = value;
 	}
 	
-	public BigInteger getDenomination() {
+	public BigInteger value() {
 		return amount;
 	}
 	
diff --git a/ethereumj-core/src/test/java/org/ethereum/core/BlockTest.java b/ethereumj-core/src/test/java/org/ethereum/core/BlockTest.java
index 2210d050..773af8dc 100644
--- a/ethereumj-core/src/test/java/org/ethereum/core/BlockTest.java
+++ b/ethereumj-core/src/test/java/org/ethereum/core/BlockTest.java
@@ -86,4 +86,16 @@ public class BlockTest {
         BlocksMessage blockData = new BlocksMessage(rlpList);
         System.out.println(blockData.toString());
     }
+    
+    @Test
+    public void testCalcDifficulty() {
+    	// Block.calcDifficulty()
+    	fail("Yet to be implemented.");
+    }
+    
+    @Test
+    public void testCalcGasLimit() {
+    	// Block.calcGasLimit()
+    	fail("Yet to be implemented.");
+    }
 }
\ No newline at end of file