4 files changed, 13 insertions, 13 deletions
diff --git a/src/primitives/block.cpp b/src/primitives/block.cpp
index 225bb80be8..3b4a360395 100644
--- a/src/primitives/block.cpp
+++ b/src/primitives/block.cpp
@@ -1,6 +1,6 @@
 // Copyright (c) 2009-2010 Satoshi Nakamoto
-// Copyright (c) 2009-2014 The Bitcoin developers
-// Distributed under the MIT/X11 software license, see the accompanying
+// Copyright (c) 2009-2014 The Bitcoin Core developers
+// Distributed under the MIT software license, see the accompanying
 // file COPYING or http://www.opensource.org/licenses/mit-license.php.
 
 #include "primitives/block.h"
@@ -74,7 +74,7 @@ uint256 CBlock::BuildMerkleTree(bool* fMutated) const
     if (fMutated) {
         *fMutated = mutated;
     }
-    return (vMerkleTree.empty() ? 0 : vMerkleTree.back());
+    return (vMerkleTree.empty() ? uint256() : vMerkleTree.back());
 }
 
 std::vector<uint256> CBlock::GetMerkleBranch(int nIndex) const
@@ -96,7 +96,7 @@ std::vector<uint256> CBlock::GetMerkleBranch(int nIndex) const
 uint256 CBlock::CheckMerkleBranch(uint256 hash, const std::vector<uint256>& vMerkleBranch, int nIndex)
 {
     if (nIndex == -1)
-        return 0;
+        return uint256();
     for (std::vector<uint256>::const_iterator it(vMerkleBranch.begin()); it != vMerkleBranch.end(); ++it)
     {
         if (nIndex & 1)
diff --git a/src/primitives/block.h b/src/primitives/block.h
index 4f2ed36b46..d77ab162e0 100644
--- a/src/primitives/block.h
+++ b/src/primitives/block.h
@@ -1,6 +1,6 @@
 // Copyright (c) 2009-2010 Satoshi Nakamoto
-// Copyright (c) 2009-2013 The Bitcoin developers
-// Distributed under the MIT/X11 software license, see the accompanying
+// Copyright (c) 2009-2013 The Bitcoin Core developers
+// Distributed under the MIT software license, see the accompanying
 // file COPYING or http://www.opensource.org/licenses/mit-license.php.
 
 #ifndef BITCOIN_PRIMITIVES_BLOCK_H
@@ -53,8 +53,8 @@ public:
     void SetNull()
     {
         nVersion = CBlockHeader::CURRENT_VERSION;
-        hashPrevBlock = 0;
-        hashMerkleRoot = 0;
+        hashPrevBlock.SetNull();
+        hashMerkleRoot.SetNull();
         nTime = 0;
         nBits = 0;
         nNonce = 0;
diff --git a/src/primitives/transaction.cpp b/src/primitives/transaction.cpp
index 336151905c..848d4d3e60 100644
--- a/src/primitives/transaction.cpp
+++ b/src/primitives/transaction.cpp
@@ -1,5 +1,5 @@
 // Copyright (c) 2009-2010 Satoshi Nakamoto
-// Copyright (c) 2009-2014 The Bitcoin developers
+// Copyright (c) 2009-2014 The Bitcoin Core developers
 // Distributed under the MIT software license, see the accompanying
 // file COPYING or http://www.opensource.org/licenses/mit-license.php.
 
@@ -72,7 +72,7 @@ void CTransaction::UpdateHash() const
     *const_cast<uint256*>(&hash) = SerializeHash(*this);
 }
 
-CTransaction::CTransaction() : hash(0), nVersion(CTransaction::CURRENT_VERSION), vin(), vout(), nLockTime(0) { }
+CTransaction::CTransaction() : nVersion(CTransaction::CURRENT_VERSION), vin(), vout(), nLockTime(0) { }
 
 CTransaction::CTransaction(const CMutableTransaction &tx) : nVersion(tx.nVersion), vin(tx.vin), vout(tx.vout), nLockTime(tx.nLockTime) {
     UpdateHash();
diff --git a/src/primitives/transaction.h b/src/primitives/transaction.h
index a7a1e013ed..1b5a47e0da 100644
--- a/src/primitives/transaction.h
+++ b/src/primitives/transaction.h
@@ -1,5 +1,5 @@
 // Copyright (c) 2009-2010 Satoshi Nakamoto
-// Copyright (c) 2009-2014 The Bitcoin developers
+// Copyright (c) 2009-2014 The Bitcoin Core developers
 // Distributed under the MIT software license, see the accompanying
 // file COPYING or http://www.opensource.org/licenses/mit-license.php.
 
@@ -28,8 +28,8 @@ public:
         READWRITE(FLATDATA(*this));
     }
 
-    void SetNull() { hash = 0; n = (uint32_t) -1; }
-    bool IsNull() const { return (hash == 0 && n == (uint32_t) -1); }
+    void SetNull() { hash.SetNull(); n = (uint32_t) -1; }
+    bool IsNull() const { return (hash.IsNull() && n == (uint32_t) -1); }
 
     friend bool operator<(const COutPoint& a, const COutPoint& b)
     {