diff --git a/src/main.cpp b/src/main.cpp
index 12bef646d..54044fe43 100644
--- a/src/main.cpp
+++ b/src/main.cpp
@@ -2218,7 +2218,7 @@ bool CBlock::CheckBlock(bool fCheckPOW, bool fCheckMerkleRoot, bool fCheckSig) c
         return DoS(50, error("CheckBlock() : proof of work failed"));
 
     // Check timestamp
-    if (GetBlockTime() > GetAdjustedTime() + nMaxClockDrift)
+    if (GetBlockTime() > GetAdjustedTime() + GetMaxClockDrift())
         return error("CheckBlock() : block timestamp too far in the future");
 
     // First transaction must be coinbase, the rest must not be
@@ -2238,7 +2238,7 @@ bool CBlock::CheckBlock(bool fCheckPOW, bool fCheckMerkleRoot, bool fCheckSig) c
         return error("CheckBlock() : coinbase output not empty for proof-of-stake block");
 	
 	// Check coinbase timestamp
-    if (GetBlockTime() > (int64)vtx[0].nTime + nMaxClockDrift)
+    if (GetBlockTime() > (int64)vtx[0].nTime + GetMaxClockDrift())
         return DoS(50, error("CheckBlock() : coinbase timestamp is too early"));
 
     // Check coinstake timestamp
@@ -2330,7 +2330,7 @@ bool CBlock::AcceptBlock()
         return DoS(100, error("AcceptBlock() : incorrect %s", IsProofOfWork() ? "proof-of-work" : "proof-of-stake"));
 
     // Check timestamp against prev
-    if (GetBlockTime() <= pindexPrev->GetMedianTimePast() || GetBlockTime() + nMaxClockDrift < pindexPrev->GetBlockTime())
+    if (GetBlockTime() <= pindexPrev->GetMedianTimePast() || GetBlockTime() + GetMaxClockDrift() < pindexPrev->GetBlockTime())
         return error("AcceptBlock() : block's timestamp is too early");
 
     // Check that all transactions are finalized
@@ -4458,7 +4458,7 @@ CBlock* CreateNewBlock(CWallet* pwallet, bool fProofOfStake, int algo)
         {
             if (pwallet->CreateCoinStake(*pwallet, pblock->nBits, nSearchTime-nLastCoinStakeSearchTime, txCoinStake))
             {
-                if (txCoinStake.nTime >= max(pindexPrev->GetMedianTimePast()+1, pindexPrev->GetBlockTime() - nMaxClockDrift))
+                if (txCoinStake.nTime >= max(pindexPrev->GetMedianTimePast()+1, pindexPrev->GetBlockTime() - GetMaxClockDrift()))
                 {   // make sure coinstake would meet timestamp protocol
                     // as it would be the same as the block timestamp
                     pblock->vtx[0].vout[0].SetEmpty();
@@ -4675,7 +4675,7 @@ CBlock* CreateNewBlock(CWallet* pwallet, bool fProofOfStake, int algo)
         if (pblock->IsProofOfStake())
             pblock->nTime      = pblock->vtx[1].nTime; //same as coinstake timestamp
         pblock->nTime          = max(pindexPrev->GetMedianTimePast()+1, pblock->GetMaxTransactionTime());
-        pblock->nTime          = max(pblock->GetBlockTime(), pindexPrev->GetBlockTime() - nMaxClockDrift);
+        pblock->nTime          = max(pblock->GetBlockTime(), pindexPrev->GetBlockTime() - GetMaxClockDrift());
         if (pblock->IsProofOfWork())
             pblock->UpdateTime(pindexPrev);
         pblock->nNonce         = 0;
@@ -4960,11 +4960,11 @@ void VERGEMiner(CWallet *pwallet, bool fProofOfStake)
 
             // Update nTime every few seconds
             pblock->nTime = max(pindexPrev->GetMedianTimePast()+1, pblock->GetMaxTransactionTime());
-            pblock->nTime = max(pblock->GetBlockTime(), pindexPrev->GetBlockTime() - nMaxClockDrift);
+            pblock->nTime = max(pblock->GetBlockTime(), pindexPrev->GetBlockTime() - GetMaxClockDrift());
             pblock->UpdateTime(pindexPrev);
             nBlockTime = ByteReverse(pblock->nTime);
 
-            if (pblock->GetBlockTime() >= (int64)pblock->vtx[0].nTime + nMaxClockDrift)
+            if (pblock->GetBlockTime() >= (int64)pblock->vtx[0].nTime + GetMaxClockDrift())
                 break;  // need to update coinbase timestamp
         }
     }
diff --git a/src/main.h b/src/main.h
index f5a3540d9..e61774569 100644
--- a/src/main.h
+++ b/src/main.h
@@ -59,7 +59,12 @@ static const int fHaveUPnP = false;
 static const uint256 hashGenesisBlockOfficial("0x00000fc63692467faeb20cdb3b53200dc601d75bdfa1001463304cc790d77278");
 static const uint256 hashGenesisBlockTestNet("0x65b4e101cacf3e1e4f3a9237e3a74ffd1186e595d8b78fa8ea22c21ef5bf9347");
 
-static const int64 nMaxClockDrift = 2 * 60 * 60;        // 2 hours
+inline int64 GetMaxClockDrift(int Height=nBestHeight){
+    if (Height < 2218500)
+        return 2 * 60 * 60; // old 2 hour drift
+    else
+        return 10 * 60; // new 10 min drift
+}
 
 extern CScript COINBASE_FLAGS;
 
diff --git a/src/rpcmining.cpp b/src/rpcmining.cpp
index bc278d536..c08b5e904 100644
--- a/src/rpcmining.cpp
+++ b/src/rpcmining.cpp
@@ -140,7 +140,7 @@ Value getworkex(const Array& params, bool fHelp)
 
         // if difficulty is high and nobody else is mining coinbase time stamp
         // will eventually expire
-        if (pblock->GetBlockTime() > (int64)pblock->vtx[0].nTime + nMaxClockDrift) {
+        if (pblock->GetBlockTime() > (int64)pblock->vtx[0].nTime + GetMaxClockDrift()) {
             int oldTime = pblock->vtx[0].nTime;
             pblock->vtx[0].nTime = GetAdjustedTime();
             pblock->hashMerkleRoot = pblock->BuildMerkleTree();
@@ -290,7 +290,7 @@ Value getwork(const Array& params, bool fHelp)
 
         // if difficulty is high and nobody else is mining coinbase time stamp
         // will eventually expire
-        if (pblock->GetBlockTime() > (int64)pblock->vtx[0].nTime + nMaxClockDrift) {
+        if (pblock->GetBlockTime() > (int64)pblock->vtx[0].nTime + GetMaxClockDrift()) {
             int oldTime = pblock->vtx[0].nTime;
             pblock->vtx[0].nTime = GetAdjustedTime();
             pblock->hashMerkleRoot = pblock->BuildMerkleTree();
@@ -434,7 +434,7 @@ Value getblocktemplate(const Array& params, bool fHelp)
 
     // if difficulty is high and nobody else is mining coinbase time stamp
     // will eventually expire
-    if (pblock->GetBlockTime() > (int64)pblock->vtx[0].nTime + nMaxClockDrift) {
+    if (pblock->GetBlockTime() > (int64)pblock->vtx[0].nTime + GetMaxClockDrift()) {
         int oldTime = pblock->vtx[0].nTime;
         pblock->vtx[0].nTime = GetAdjustedTime();
         pblock->hashMerkleRoot = pblock->BuildMerkleTree();