diff --git a/mailpile/mail_source/imap.py b/mailpile/mail_source/imap.py
index f5b736a8f..b36f2ff84 100644
--- a/mailpile/mail_source/imap.py
+++ b/mailpile/mail_source/imap.py
@@ -334,7 +334,7 @@ def get_line():
             raise self._conn.abort('socket error: %s' % val)
 
     def quit(self):
-        self._can_idle = False
+        self._can_idle = False  # Required to avoid deadlock below
         with self._lock:
             try:
                 if self._conn and self._conn.file: