diff --git a/src/tools/pgcvslog b/src/tools/pgcvslog
index b602880ceb0..0ee43b5041a 100755
--- a/src/tools/pgcvslog
+++ b/src/tools/pgcvslog
@@ -15,6 +15,9 @@
 # date range
 # cvs log -d'2005-05-08<2005-05-29' -b .
 #
+# To find branch time, look for "branches:" tag in CVS commit logs
+# e.g. "branches:  1.398.4;" matches "REL8_0_STABLE: 1.398.0.4".
+#
 # Remove TODO and FAQ logs if desired
 #