diff --git a/chainlib/eth/contract.py b/chainlib/eth/contract.py
index a609334..87466c4 100644
--- a/chainlib/eth/contract.py
+++ b/chainlib/eth/contract.py
@@ -77,7 +77,7 @@ class ABIMethodEncoder(ABIContract):
 
 
 
-class ABIContractDecoder:
+class ABIContractDecoder(ABIContract):
 
     
     def typ(self, v):
@@ -137,7 +137,8 @@ class ABIContractDecoder:
             m = getattr(self, self.types[i])
             s = self.contents[i]
             logg.debug('{} {} {} {} {}'.format(i, m, self.types[i], self.contents[i], s))
-            r.append(m(s.hex()))
+            #r.append(m(s.hex()))
+            r.append(m(s))
         return r
 
 
diff --git a/chainlib/eth/tx.py b/chainlib/eth/tx.py
index 085c25a..f89d431 100644
--- a/chainlib/eth/tx.py
+++ b/chainlib/eth/tx.py
@@ -117,7 +117,10 @@ def unpack_hex(tx_raw_bytes, chain_spec):
 
 
 def __unpack_raw(tx_raw_bytes, chain_id=1):
-    d = rlp_decode(tx_raw_bytes)
+    try:
+        d = rlp_decode(tx_raw_bytes)
+    except Exception as e:
+        raise ValueError('RLP deserialization failed: {}'.format(e))
 
     logg.debug('decoding using chain id {}'.format(str(chain_id)))
     
diff --git a/tests/test_event.py b/tests/test_event.py
index 9c749fa..2e4c373 100644
--- a/tests/test_event.py
+++ b/tests/test_event.py
@@ -23,15 +23,15 @@ class TestContractLog(EthTesterCase):
         n = 42
         topics = [
                 s,
-                n.to_bytes(32, byteorder='big'),
+                n.to_bytes(32, byteorder='big').hex(),
                 ]
         data = [
-            (b'\xee' * 32),
+            (b'\xee' * 32).hex(),
                 ]
         dec.apply(topics, data)
         o = dec.decode()
         self.assertEqual(o[0], 42)
-        self.assertEqual(o[1], data[0].hex())
+        self.assertEqual(o[1], data[0])
 
 
 if __name__ == '__main__':