diff --git a/src/error.rs b/src/error.rs
index cdc0c2d25..4ca988679 100644
--- a/src/error.rs
+++ b/src/error.rs
@@ -120,7 +120,9 @@ pub enum BlockError {
 	/// TODO [arkpar] Please document me
 	InvalidParentHash(Mismatch<H256>),
 	/// TODO [arkpar] Please document me
-	InvalidNumber(OutOfBounds<BlockNumber>),
+	InvalidNumber(Mismatch<BlockNumber>),
+	/// Block number isn't sensible.
+	RidiculousNumber(OutOfBounds<BlockNumber>),
 	/// TODO [arkpar] Please document me
 	UnknownParent(H256),
 	/// TODO [Gav Wood] Please document me
diff --git a/src/tests/chain.rs b/src/tests/chain.rs
index 894303a4c..dfc46ae5a 100644
--- a/src/tests/chain.rs
+++ b/src/tests/chain.rs
@@ -42,6 +42,9 @@ fn do_json_test(json_data: &[u8]) -> Vec<String> {
 					client.flush_queue();
 					let imported_ok = client.import_verified_blocks(&IoChannel::disconnected()) > 0;
 					assert_eq!(imported_ok, is_valid);
+					if imported_ok {
+						flushln!("Imported {}; best block {}", hash, client.chain_info().best_block_hash);
+					}
 				}
 				fail_unless(client.chain_info().best_block_hash == H256::from_json(&test["lastblockhash"]));
 			}
@@ -60,13 +63,13 @@ declare_test!{BlockchainTests_bcForkBlockTest, "BlockchainTests/bcForkBlockTest"
 declare_test!{BlockchainTests_bcForkStressTest, "BlockchainTests/bcForkStressTest"}				// STILL FAILS
 declare_test!{BlockchainTests_bcForkUncle, "BlockchainTests/bcForkUncle"}						// STILL FAILS
 declare_test!{BlockchainTests_bcGasPricerTest, "BlockchainTests/bcGasPricerTest"}
-declare_test!{BlockchainTests_bcInvalidHeaderTest, "BlockchainTests/bcInvalidHeaderTest"}
+declare_test!{BlockchainTests_bcInvalidHeaderTest, "BlockchainTests/bcInvalidHeaderTest"}		// FAILS AGAIN?
 declare_test!{BlockchainTests_bcInvalidRLPTest, "BlockchainTests/bcInvalidRLPTest"}
 declare_test!{BlockchainTests_bcMultiChainTest, "BlockchainTests/bcMultiChainTest"}
 declare_test!{BlockchainTests_bcRPC_API_Test, "BlockchainTests/bcRPC_API_Test"}
 declare_test!{BlockchainTests_bcStateTest, "BlockchainTests/bcStateTest"}
-declare_test!{BlockchainTests_bcTotalDifficultyTest, "BlockchainTests/bcTotalDifficultyTest"}
-declare_test!{BlockchainTests_bcUncleHeaderValiditiy, "BlockchainTests/bcUncleHeaderValiditiy"}	// FAILS
-declare_test!{BlockchainTests_bcUncleTest, "BlockchainTests/bcUncleTest"}						// FAILS
-declare_test!{BlockchainTests_bcValidBlockTest, "BlockchainTests/bcValidBlockTest"}				// FAILS
-declare_test!{BlockchainTests_bcWalletTest, "BlockchainTests/bcWalletTest"}						// FAILS
+declare_test!{BlockchainTests_bcTotalDifficultyTest, "BlockchainTests/bcTotalDifficultyTest"}	// FAILS AGAIN?
+declare_test!{BlockchainTests_bcUncleHeaderValiditiy, "BlockchainTests/bcUncleHeaderValiditiy"}
+declare_test!{BlockchainTests_bcUncleTest, "BlockchainTests/bcUncleTest"}
+declare_test!{BlockchainTests_bcValidBlockTest, "BlockchainTests/bcValidBlockTest"}				// STILL FAILS
+declare_test!{BlockchainTests_bcWalletTest, "BlockchainTests/bcWalletTest"}
diff --git a/src/verification.rs b/src/verification.rs
index 064c0b7d7..158f28f95 100644
--- a/src/verification.rs
+++ b/src/verification.rs
@@ -162,7 +162,7 @@ pub fn verify_block_final(expected: &Header, got: &Header) -> Result<(), Error>
 /// Check basic header parameters.
 fn verify_header(header: &Header, engine: &Engine) -> Result<(), Error> {
 	if header.number >= From::from(BlockNumber::max_value()) {
-		return Err(From::from(BlockError::InvalidNumber(OutOfBounds { max: Some(From::from(BlockNumber::max_value())), min: None, found: header.number })))
+		return Err(From::from(BlockError::RidiculousNumber(OutOfBounds { max: Some(From::from(BlockNumber::max_value())), min: None, found: header.number })))
 	}
 	if header.gas_used > header.gas_limit {
 		return Err(From::from(BlockError::TooMuchGasUsed(OutOfBounds { max: Some(header.gas_limit), min: None, found: header.gas_used })));
@@ -186,8 +186,8 @@ fn verify_parent(header: &Header, parent: &Header) -> Result<(), Error> {
 	if header.timestamp <= parent.timestamp {
 		return Err(From::from(BlockError::InvalidTimestamp(OutOfBounds { max: None, min: Some(parent.timestamp + 1), found: header.timestamp })))
 	}
-	if header.number <= parent.number {
-		return Err(From::from(BlockError::InvalidNumber(OutOfBounds { max: None, min: Some(parent.number + 1), found: header.number })));
+	if header.number != parent.number + 1 {
+		return Err(From::from(BlockError::InvalidNumber(Mismatch { expected: parent.number + 1, found: header.number })));
 	}
 	Ok(())
 }
@@ -400,7 +400,7 @@ mod tests {
 		header = good.clone();
 		header.number = BlockNumber::max_value();
 		check_fail(basic_test(&create_test_block(&header), engine.deref()),
-			InvalidNumber(OutOfBounds { max: Some(BlockNumber::max_value()), min: None, found: header.number }));
+			RidiculousNumber(OutOfBounds { max: Some(BlockNumber::max_value()), min: None, found: header.number }));
 
 		header = good.clone();
 		header.gas_used = header.gas_limit + From::from(1);
@@ -443,7 +443,7 @@ mod tests {
 		header = good.clone();
 		header.number = 9;
 		check_fail(family_test(&create_test_block_with_data(&header, &good_transactions, &good_uncles), engine.deref(), &bc),
-			InvalidNumber(OutOfBounds { max: None, min: Some(parent.number + 1), found: header.number }));
+			InvalidNumber(Mismatch { expected: parent.number + 1, found: header.number }));
 		
 		header = good.clone();
 		let mut bad_uncles = good_uncles.clone();