diff --git a/test/functional/abc-p2p-compactblocks.py b/test/functional/abc-p2p-compactblocks.py
--- a/test/functional/abc-p2p-compactblocks.py
+++ b/test/functional/abc-p2p-compactblocks.py
@@ -15,6 +15,7 @@
 from test_framework.util import *
 from test_framework.comptool import TestManager, TestInstance, RejectResult
 from test_framework.blocktools import *
+from test_framework.txtools import pad_tx
 import time
 from test_framework.script import *
 from test_framework.cdefs import (ONE_MEGABYTE, LEGACY_MAX_BLOCK_SIZE,
@@ -97,7 +98,7 @@
         self.test.run()
 
     def add_transactions_to_block(self, block, tx_list):
-        [tx.rehash() for tx in tx_list]
+        [pad_tx(tx) for tx in tx_list]
         block.vtx.extend(tx_list)
 
     # this is a little handier to use than the version in blocktools.py