Possible workaround for crash

src/wallet/wallet.cpp

@@ -1885,6 +1885,11 @@ void CWallet::ReacceptWalletTransactions()
 
 bool CWalletTx::RelayWalletTransaction()
 {
+    if ( pwallet == 0 )
+    {
+        fprintf(stderr,"unexpected null pwallet in RelayWalletTransaction\n");
+        return(false);
+    }
     assert(pwallet->GetBroadcastTransactions());
     if (!IsCoinBase())
     {
@@ -2124,9 +2129,13 @@ std::vector<uint256> CWallet::ResendWalletTransactionsBefore(int64_t nTime)
     }
     BOOST_FOREACH(PAIRTYPE(const unsigned int, CWalletTx*)& item, mapSorted)
     {
-        CWalletTx& wtx = *item.second;
-        if (wtx.RelayWalletTransaction())
-            result.push_back(wtx.GetHash());
+        CWalletTx& wtx;
+        if ( item.second != 0 )
+        {
+            wtx = *item.second;
+            if (wtx.RelayWalletTransaction())
+                result.push_back(wtx.GetHash());
+        }
     }
     return result;
 }