diff --git a/src/chain.h b/src/chain.h
index 1c2d89933b..a8a6b4dd64 100644
--- a/src/chain.h
+++ b/src/chain.h
@@ -236,14 +236,6 @@ public:
         return pbegin[(pend - pbegin)/2];
     }
 
-    /**
-     * Returns true if there are nRequired or more blocks of minVersion or above
-     * in the last Params().ToCheckBlockUpgradeMajority() blocks, starting at pstart 
-     * and going backwards.
-     */
-    static bool IsSuperMajority(int minVersion, const CBlockIndex* pstart,
-                                unsigned int nRequired);
-
     std::string ToString() const
     {
         return strprintf("CBlockIndex(pprev=%p, nHeight=%d, merkle=%s, hashBlock=%s)",
diff --git a/src/main.cpp b/src/main.cpp
index 50e63e93e4..bc08c3ea29 100644
--- a/src/main.cpp
+++ b/src/main.cpp
@@ -67,6 +67,13 @@ map<uint256, COrphanTx> mapOrphanTransactions;
 map<uint256, set<uint256> > mapOrphanTransactionsByPrev;
 void EraseOrphansFor(NodeId peer);
 
+/**
+ * Returns true if there are nRequired or more blocks of minVersion or above
+ * in the last Params().ToCheckBlockUpgradeMajority() blocks, starting at pstart 
+ * and going backwards.
+ */
+static bool IsSuperMajority(int minVersion, const CBlockIndex* pstart, unsigned int nRequired);
+
 /** Constant stuff for coinbase transactions we create: */
 CScript COINBASE_FLAGS;
 
@@ -2479,8 +2486,7 @@ bool ContextualCheckBlockHeader(const CBlockHeader& block, CValidationState& sta
         return state.DoS(100, error("%s : forked chain older than last checkpoint (height %d)", __func__, nHeight));
 
     // Reject block.nVersion=1 blocks when 95% (75% on testnet) of the network has upgraded:
-    if (block.nVersion < 2 && 
-        CBlockIndex::IsSuperMajority(2, pindexPrev, Params().RejectBlockOutdatedMajority()))
+    if (block.nVersion < 2 && IsSuperMajority(2, pindexPrev, Params().RejectBlockOutdatedMajority()))
     {
         return state.Invalid(error("%s : rejected nVersion=1 block", __func__),
                              REJECT_OBSOLETE, "bad-version");
@@ -2501,8 +2507,7 @@ bool ContextualCheckBlock(const CBlock& block, CValidationState& state, CBlockIn
 
     // Enforce block.nVersion=2 rule that the coinbase starts with serialized block height
     // if 750 of the last 1,000 blocks are version 2 or greater (51/100 if testnet):
-    if (block.nVersion >= 2 && 
-        CBlockIndex::IsSuperMajority(2, pindexPrev, Params().EnforceBlockUpgradeMajority()))
+    if (block.nVersion >= 2 && IsSuperMajority(2, pindexPrev, Params().EnforceBlockUpgradeMajority()))
     {
         CScript expect = CScript() << nHeight;
         if (block.vtx[0].vin[0].scriptSig.size() < expect.size() ||
@@ -2600,7 +2605,7 @@ bool AcceptBlock(CBlock& block, CValidationState& state, CBlockIndex** ppindex,
     return true;
 }
 
-bool CBlockIndex::IsSuperMajority(int minVersion, const CBlockIndex* pstart, unsigned int nRequired)
+static bool IsSuperMajority(int minVersion, const CBlockIndex* pstart, unsigned int nRequired)
 {
     unsigned int nToCheck = Params().ToCheckBlockUpgradeMajority();
     unsigned int nFound = 0;