diff --git a/cyrus-imapd.spec b/cyrus-imapd.spec
index 7c6eccf..9d2b975 100644
--- a/cyrus-imapd.spec
+++ b/cyrus-imapd.spec
@@ -70,6 +70,8 @@ Source91: patch-cassandane-no-syslog
 # Tell the annotator script to run as the current user/group
 # Upstream ticket https://github.com/cyrusimap/cyrus-imapd/issues/1995
 Source92: patch-cassandane-fix-annotator
+## Upstream commit:
+## https://github.com/cyrusimap/cassandane/commit/2221787bf86cb886b878eb844e81829165f3ed15
 Source93: patch-cassandane-unknown_calendars
 
 # Dependency notes: