1 files changed, 8 insertions, 8 deletions
diff --git a/packages/contracts/src/contracts/current/protocol/Exchange/MixinTransactions.sol b/packages/contracts/src/contracts/current/protocol/Exchange/MixinTransactions.sol
index d153dfa5c..30b0102fd 100644
--- a/packages/contracts/src/contracts/current/protocol/Exchange/MixinTransactions.sol
+++ b/packages/contracts/src/contracts/current/protocol/Exchange/MixinTransactions.sol
@@ -17,9 +17,9 @@
 */
 pragma solidity ^0.4.24;
 
+import "./libs/LibExchangeErrors.sol";
 import "./mixins/MSignatureValidator.sol";
 import "./mixins/MTransactions.sol";
-import "./libs/LibExchangeErrors.sol";
 
 contract MixinTransactions is
     LibExchangeErrors,
@@ -50,29 +50,29 @@ contract MixinTransactions is
         // Prevent reentrancy
         require(
             currentContextAddress == address(0),
-            REENTRANCY_NOT_ALLOWED
+            REENTRANCY_ILLEGAL
         );
 
         // Calculate transaction hash
-        bytes32 transactionHash = keccak256(
+        bytes32 transactionHash = keccak256(abi.encodePacked(
             address(this),
             signer,
             salt,
             data
-        );
+        ));
 
         // Validate transaction has not been executed
         require(
             !transactions[transactionHash],
-            DUPLICATE_TRANSACTION_HASH
+            INVALID_TX_HASH
         );
 
-        // TODO: is SignatureType.Caller necessary if we make this check?
+        // Transaction always valid if signer is sender of transaction
         if (signer != msg.sender) {
             // Validate signature
             require(
                 isValidSignature(transactionHash, signer, signature),
-                SIGNATURE_VALIDATION_FAILED
+                INVALID_TX_SIGNATURE
             );
 
             // Set the current transaction signer
@@ -83,7 +83,7 @@ contract MixinTransactions is
         transactions[transactionHash] = true;
         require(
             address(this).delegatecall(data),
-            TRANSACTION_EXECUTION_FAILED
+            FAILED_EXECUTION
         );
 
         // Reset current transaction signer