diff --git a/src/server/poolserver/Stratum/Client.cpp b/src/server/poolserver/Stratum/Client.cpp
index 4029dc2..392af9a 100644
--- a/src/server/poolserver/Stratum/Client.cpp
+++ b/src/server/poolserver/Stratum/Client.cpp
@@ -359,7 +359,6 @@ namespace Stratum
                         sLog.Error(LOG_SERVER, "Exception caught while parsing json: %s", e.what());
                     }
                     _recvMessage.clear();
-                    _recvMessage.reserve(PACKET_ALLOC);
                 } else
                     _recvMessage += c;
             }
diff --git a/src/server/poolserver/Stratum/Client.h b/src/server/poolserver/Stratum/Client.h
index a929f34..ff873aa 100644
--- a/src/server/poolserver/Stratum/Client.h
+++ b/src/server/poolserver/Stratum/Client.h
@@ -15,8 +15,6 @@
 #include <boost/enable_shared_from_this.hpp>
 #include <set>
 
-#define PACKET_ALLOC 128
-
 using namespace boost;
 using namespace boost::asio::ip;
 
@@ -31,7 +29,6 @@ namespace Stratum
         {
             _diff = sConfig.Get<uint32>("StratumMinDifficulty");
             _minDiff = _diff;
-            _recvMessage.reserve(PACKET_ALLOC);
         }
         
         tcp::socket& GetSocket()
diff --git a/src/server/poolserver/Stratum/ShareLimiter.cpp b/src/server/poolserver/Stratum/ShareLimiter.cpp
index 3cad777..d291296 100644
--- a/src/server/poolserver/Stratum/ShareLimiter.cpp
+++ b/src/server/poolserver/Stratum/ShareLimiter.cpp
@@ -21,11 +21,14 @@ namespace Stratum
         _lastRetarget = curTime;
         
         // Check if miner is ok
-        if (_totalShares > 20 && (double(_totalBadShares)/double(_totalShares)) > 0.8)
+        if (_totalShares > 50 && (double(_totalBadShares)/double(_totalShares)) > 0.8)
             _client->Ban(60);
         
-        while (_shares.size() && (_shares.front() < curTime - RETARGET_TIME_BUFFER))
+        while (_shares.size()) {
+            if (_shares.front() > curTime - RETARGET_TIME_BUFFER)
+                break;
             _shares.pop_front();
+        }
         
         uint32 interval = std::min(curTime - _startTime, uint64(RETARGET_TIME_BUFFER));
         
diff --git a/src/server/shared/Bitcoin/Bitcoin.h b/src/server/shared/Bitcoin/Bitcoin.h
index eadf469..af2e344 100644
--- a/src/server/shared/Bitcoin/Bitcoin.h
+++ b/src/server/shared/Bitcoin/Bitcoin.h
@@ -28,7 +28,9 @@ namespace Bitcoin
         mpz_t power;
         mpz_init(power);
         mpz_ui_pow_ui(power, 2, 8 * (nbytes - 3));
-        return BigInt(bits & 0xFFFFFF) * BigInt(power);
+        BigInt result = BigInt(bits & 0xFFFFFF) * BigInt(power);
+        mpz_clear(power);
+        return result;
     }
     
     inline Transaction CreateCoinbaseTX(uint32 blockHeight, BinaryData pubkey, int64 value)
diff --git a/src/server/shared/JSON/JSONReader.h b/src/server/shared/JSON/JSONReader.h
index 1af48a0..fa66894 100644
--- a/src/server/shared/JSON/JSONReader.h
+++ b/src/server/shared/JSON/JSONReader.h
@@ -22,6 +22,14 @@ namespace JSONReader
             _stack.push_back(&node);
         }
         
+        ~SemanticFunctions()
+        {
+            for (uint32 i = 0; i+1 < _stack.size(); ++i) {
+                delete _stack.back();
+                _stack.pop_back();
+            } 
+        }
+        
         void BeginObject(char ch)
         {
             if (_stack.back()->GetType() == JSON_NULL)
diff --git a/src/server/shared/MySQL/DatabaseConnection.h b/src/server/shared/MySQL/DatabaseConnection.h
index a9936b6..08bedd8 100644
--- a/src/server/shared/MySQL/DatabaseConnection.h
+++ b/src/server/shared/MySQL/DatabaseConnection.h
@@ -87,7 +87,7 @@ namespace MySQL
             char* buf = new char[text.length()*2 + 1];
             mysql_real_escape_string(_mysql, buf, text.c_str(), text.length());
             std::string result(buf);
-            delete buf;
+            delete[] buf;
             return result;
         }
         
diff --git a/src/server/shared/MySQL/DatabaseOperation.cpp b/src/server/shared/MySQL/DatabaseOperation.cpp
index d3598df..63dd8fb 100644
--- a/src/server/shared/MySQL/DatabaseOperation.cpp
+++ b/src/server/shared/MySQL/DatabaseOperation.cpp
@@ -21,9 +21,9 @@ namespace MySQL
     void DatabaseQueryOperation::Execute()
     {
         if (_callback) {
-            ResultSet* result = _conn->Query(_query);
+            ResultSet* result = _conn->Query(_query.c_str());
             _callback(QueryResult(result));
         } else
-            _conn->Execute(_query);
+            _conn->Execute(_query.c_str());
     }
 }
diff --git a/src/server/shared/MySQL/DatabaseOperation.h b/src/server/shared/MySQL/DatabaseOperation.h
index ccc953a..3e8f05b 100644
--- a/src/server/shared/MySQL/DatabaseOperation.h
+++ b/src/server/shared/MySQL/DatabaseOperation.h
@@ -40,22 +40,15 @@ namespace MySQL
     class DatabaseQueryOperation : public DatabaseOperation
     {
     public:
-        DatabaseQueryOperation(const char* query, DatabaseCallback callback = NULL): DatabaseOperation(), _callback(callback)
-        {
-            _query = new char[strlen(query)];
-            strcpy(_query, const_cast<char *>(query));
-        }
+        DatabaseQueryOperation(const char* query, DatabaseCallback callback = NULL): DatabaseOperation(), _callback(callback), _query(query) {}
         
-        ~DatabaseQueryOperation()
-        {
-            delete[] _query;
-        }
+        ~DatabaseQueryOperation() {}
         
         void Execute();
 
     private:
         DatabaseCallback _callback;
-        char* _query;
+        std::string _query;
     };
 
     typedef Util::SynchronisedQueue<DatabaseOperation*> DatabaseWorkQueue;
diff --git a/src/server/shared/MySQL/DatabaseWorkerPool.h b/src/server/shared/MySQL/DatabaseWorkerPool.h
index c8f1dc4..62dd709 100644
--- a/src/server/shared/MySQL/DatabaseWorkerPool.h
+++ b/src/server/shared/MySQL/DatabaseWorkerPool.h
@@ -104,7 +104,7 @@ namespace MySQL
     private:
         DatabaseConnection* GetSyncConnection()
         {
-            uint32 i;
+            uint32 i = 0;
             uint8 conn_size = _connections[MYSQL_CONN_SYNC].size();
             DatabaseConnection* conn = NULL;