diff --git a/src/bitcoinrpc.cpp b/src/bitcoinrpc.cpp
index 5d38f042f..cf5bc64bb 100644
--- a/src/bitcoinrpc.cpp
+++ b/src/bitcoinrpc.cpp
@@ -353,7 +353,7 @@ Value getinfo(const Array& params, bool fHelp)
     obj.push_back(Pair("keypoolsize",   pwalletMain->GetKeyPoolSize()));
     obj.push_back(Pair("paytxfee",      ValueFromAmount(nTransactionFee)));
     if (pwalletMain->IsCrypted())
-        obj.push_back(Pair("unlocked_until", (boost::int64_t)nWalletUnlockTime));
+        obj.push_back(Pair("unlocked_until", (boost::int64_t)nWalletUnlockTime / 1000));
     obj.push_back(Pair("errors",        GetWarnings("statusbar")));
     return obj;
 }
@@ -1537,35 +1537,41 @@ void ThreadTopUpKeyPool(void* parg)
 
 void ThreadCleanWalletPassphrase(void* parg)
 {
-    int64 nMyWakeTime = GetTime() + *((int*)parg);
+    int64 nMyWakeTime = GetTimeMillis() + *((int*)parg) * 1000;
+
+    ENTER_CRITICAL_SECTION(cs_nWalletUnlockTime);
 
     if (nWalletUnlockTime == 0)
     {
-        CRITICAL_BLOCK(cs_nWalletUnlockTime)
+        nWalletUnlockTime = nMyWakeTime;
+
+        do
         {
-            nWalletUnlockTime = nMyWakeTime;
-        }
+            if (nWalletUnlockTime==0)
+                break;
+            int64 nToSleep = nWalletUnlockTime - GetTimeMillis();
+            if (nToSleep <= 0)
+                break;
 
-        while (GetTime() < nWalletUnlockTime)
-            Sleep(GetTime() - nWalletUnlockTime);
+            LEAVE_CRITICAL_SECTION(cs_nWalletUnlockTime);
+            Sleep(nToSleep);
+            ENTER_CRITICAL_SECTION(cs_nWalletUnlockTime);
 
-        CRITICAL_BLOCK(cs_nWalletUnlockTime)
+        } while(1);
+
+        if (nWalletUnlockTime)
         {
             nWalletUnlockTime = 0;
+            pwalletMain->Lock();
         }
     }
     else
     {
-        CRITICAL_BLOCK(cs_nWalletUnlockTime)
-        {
-            if (nWalletUnlockTime < nMyWakeTime)
-                nWalletUnlockTime = nMyWakeTime;
-        }
-        delete (int*)parg;
-        return;
+        if (nWalletUnlockTime < nMyWakeTime)
+            nWalletUnlockTime = nMyWakeTime;
     }
 
-    pwalletMain->Lock();
+    LEAVE_CRITICAL_SECTION(cs_nWalletUnlockTime);
 
     delete (int*)parg;
 }
@@ -1655,9 +1661,9 @@ Value walletlock(const Array& params, bool fHelp)
     if (!pwalletMain->IsCrypted())
         throw JSONRPCError(-15, "Error: running with an unencrypted wallet, but walletlock was called.");
 
-    pwalletMain->Lock();
     CRITICAL_BLOCK(cs_nWalletUnlockTime)
     {
+        pwalletMain->Lock();
         nWalletUnlockTime = 0;
     }
 
diff --git a/src/net.h b/src/net.h
index 2be9541cd..a66bc1543 100644
--- a/src/net.h
+++ b/src/net.h
@@ -279,7 +279,7 @@ public:
 
     void BeginMessage(const char* pszCommand)
     {
-        cs_vSend.Enter("cs_vSend", __FILE__, __LINE__);
+        ENTER_CRITICAL_SECTION(cs_vSend);
         if (nHeaderStart != -1)
             AbortMessage();
         nHeaderStart = vSend.size();
@@ -298,7 +298,7 @@ public:
         vSend.resize(nHeaderStart);
         nHeaderStart = -1;
         nMessageStart = -1;
-        cs_vSend.Leave();
+        LEAVE_CRITICAL_SECTION(cs_vSend);
 
         if (fDebug)
             printf("(aborted)\n");
@@ -336,7 +336,7 @@ public:
 
         nHeaderStart = -1;
         nMessageStart = -1;
-        cs_vSend.Leave();
+        LEAVE_CRITICAL_SECTION(cs_vSend);
     }
 
     void EndMessageAbortIfEmpty()
diff --git a/src/util.h b/src/util.h
index 8dcedb147..ddc8791b3 100644
--- a/src/util.h
+++ b/src/util.h
@@ -218,6 +218,12 @@ public:
 #define CRITICAL_BLOCK(cs)     \
     if (CCriticalBlock criticalblock = CCriticalBlock(cs, #cs, __FILE__, __LINE__))
 
+#define ENTER_CRITICAL_SECTION(cs) \
+    (cs).Enter(#cs, __FILE__, __LINE__)
+
+#define LEAVE_CRITICAL_SECTION(cs) \
+    (cs).Leave()
+
 class CTryCriticalBlock
 {
 protected: