diff --git a/hgext/patchbomb.py b/hgext/patchbomb.py
--- a/hgext/patchbomb.py
+++ b/hgext/patchbomb.py
@@ -74,6 +74,7 @@
 from __future__ import absolute_import
 
 import email as emailmod
+import email.utils as eutil
 import errno
 import os
 import socket
@@ -744,7 +745,7 @@
         if not parent.endswith('>'):
             parent += '>'
 
-    sender_addr = emailmod.Utils.parseaddr(sender)[1]
+    sender_addr = eutil.parseaddr(pycompat.sysstr(sender))[1]
     sender = mail.addressencode(ui, sender, _charsets, opts.get('test'))
     sendmail = None
     firstpatch = None
@@ -763,7 +764,7 @@
             parent = m['Message-Id']
 
         m['User-Agent'] = 'Mercurial-patchbomb/%s' % util.version()
-        m['Date'] = emailmod.Utils.formatdate(start_time[0], localtime=True)
+        m['Date'] = eutil.formatdate(start_time[0], localtime=True)
 
         start_time = (start_time[0] + 1, start_time[1])
         m['From'] = sender