diff --git a/src/main.cpp b/src/main.cpp
index 0c31655f..f2e6b67f 100644
--- a/src/main.cpp
+++ b/src/main.cpp
@@ -3278,6 +3278,8 @@ void static ProcessGetData(CNode* pfrom)
 
     vector<CInv> vNotFound;
 
+    LOCK(cs_main);
+
     while (it != pfrom->vRecvGetData.end()) {
         // Don't bother if send buffer is too full to respond anyway
         if (pfrom->nSendSize >= SendBufferSize())
@@ -3450,7 +3452,6 @@ bool static ProcessMessage(CNode* pfrom, string strCommand, CDataStream& vRecv)
 
         pfrom->fClient = !(pfrom->nServices & NODE_NETWORK);
 
-        AddTimeData(pfrom->addr, nTime);
 
         // Change version
         pfrom->PushMessage("verack");
@@ -3492,6 +3493,8 @@ bool static ProcessMessage(CNode* pfrom, string strCommand, CDataStream& vRecv)
 
         LogPrintf("receive version message: version %d, blocks=%d, us=%s, them=%s, peer=%s\n", pfrom->nVersion, pfrom->nStartingHeight, addrMe.ToString().c_str(), addrFrom.ToString().c_str(), pfrom->addr.ToString().c_str());
 
+        LOCK(cs_main);
+        AddTimeData(pfrom->addr, nTime);
         cPeerBlockCounts.input(pfrom->nStartingHeight);
     }
 
@@ -3595,6 +3598,9 @@ bool static ProcessMessage(CNode* pfrom, string strCommand, CDataStream& vRecv)
                 break;
             }
         }
+
+        LOCK(cs_main);
+
         for (unsigned int nInv = 0; nInv < vInv.size(); nInv++)
         {
             const CInv &inv = vInv[nInv];
@@ -3652,6 +3658,8 @@ bool static ProcessMessage(CNode* pfrom, string strCommand, CDataStream& vRecv)
         uint256 hashStop;
         vRecv >> locator >> hashStop;
 
+        LOCK(cs_main);
+
         // Find the last block the caller has in the main chain
         CBlockIndex* pindex = locator.GetBlockIndex();
 
@@ -3686,6 +3694,8 @@ bool static ProcessMessage(CNode* pfrom, string strCommand, CDataStream& vRecv)
         uint256 hashStop;
         vRecv >> locator >> hashStop;
 
+        LOCK(cs_main);
+
         CBlockIndex* pindex = NULL;
         if (locator.IsNull())
         {
@@ -3728,6 +3738,8 @@ bool static ProcessMessage(CNode* pfrom, string strCommand, CDataStream& vRecv)
         CInv inv(MSG_TX, tx.GetHash());
         pfrom->AddInventoryKnown(inv);
 
+        LOCK(cs_main);
+
         bool fMissingInputs = false;
         CValidationState state;
         if (mempool.accept(state, tx, true, &fMissingInputs))
@@ -3802,6 +3814,8 @@ bool static ProcessMessage(CNode* pfrom, string strCommand, CDataStream& vRecv)
         CInv inv(MSG_BLOCK, block.GetHash());
         pfrom->AddInventoryKnown(inv);
 
+        LOCK(cs_main);
+
         CValidationState state;
         if (ProcessBlock(state, pfrom, &block))
             mapAlreadyAskedFor.erase(inv);
@@ -3823,6 +3837,8 @@ bool static ProcessMessage(CNode* pfrom, string strCommand, CDataStream& vRecv)
 
     else if (strCommand == "mempool")
     {
+        LOCK(cs_main);
+
         std::vector<uint256> vtxid;
         LOCK2(mempool.cs, pfrom->cs_filter);
         mempool.queryHashes(vtxid);
@@ -4088,10 +4104,7 @@ bool ProcessMessages(CNode* pfrom)
         bool fRet = false;
         try
         {
-            {
-                LOCK(cs_main);
-                fRet = ProcessMessage(pfrom, strCommand, vRecv);
-            }
+            fRet = ProcessMessage(pfrom, strCommand, vRecv);
             boost::this_thread::interruption_point();
         }
         catch (std::ios_base::failure& e)