      CTransaction()
      {
          SetNull();
+@@ -416,6 +426,7 @@ public:
+         vout.clear();
+         nLockTime = 0;
+         nDoS = 0;  // Denial-of-service prevention
 +	set_electrum_flag(false);
      }
  
-     IMPLEMENT_SERIALIZE
+     bool IsNull() const

 Value backupwallet(const Array& params, bool fHelp)
 {
     if (fHelp || params.size() != 1)
@@ -2055,6 +2092,7 @@ static const CRPCCommand vRPCCommands[] =
     { "listsinceblock",         &listsinceblock,         false },
     { "dumpprivkey",            &dumpprivkey,            false },
     { "importprivkey",          &importprivkey,          false },

 
 CRPCTable::CRPCTable()
diff --git a/src/main.cpp b/src/main.cpp
index 427e435..19236ac 100644
--- a/src/main.cpp
+++ b/src/main.cpp
@@ -3222,18 +3222,21 @@ CBlock* CreateNewBlock(CReserveKey& reservekey)
 
             // Size limits
             unsigned int nTxSize = ::GetSerializeSize(tx, SER_NETWORK, PROTOCOL_VERSION);
