2 files changed, 2 insertions, 2 deletions

diff --git a/src/mailman/handlers/subject_prefix.py b/src/mailman/handlers/subject_prefix.py
index ff728d92e..20f47fc5d 100644
--- a/src/mailman/handlers/subject_prefix.py
+++ b/src/mailman/handlers/subject_prefix.py
@@ -162,7 +162,7 @@ class SubjectPrefix:
         if p.search(prefix, 1):
             # The prefix has number, so we should search prefix w/number in
             # subject.  Also, force new style.
-            prefix_pattern = p.sub(r'\s*\d+\s*', prefix_pattern)
+            prefix_pattern = p.sub(r'\\s*\\d+\\s*', prefix_pattern)
         # Substitute %d in prefix with post_id
         with suppress(TypeError):
             prefix = prefix % mlist.post_id
diff --git a/src/mailman/testing/mta.py b/src/mailman/testing/mta.py
index c1327f428..fbbb890d8 100644
--- a/src/mailman/testing/mta.py
+++ b/src/mailman/testing/mta.py
@@ -183,7 +183,7 @@ class ConnectionCountingServer(QueueServer):
         log.info('[ConnectionCountingServer] accepted: %s', address)
         StatisticsChannel(self, connection, address)
 
-    def process_message(self, peer, mailfrom, rcpttos, data):
+    def process_message(self, peer, mailfrom, rcpttos, data, **kwargs):
         # Provide a guaranteed order to recpttos.
         QueueServer.process_message(
             self, peer, mailfrom, sorted(rcpttos), data)