Index: branches/5.1.x/core/install/upgrades.sql
===================================================================
diff -u -r13811 -r13816
--- branches/5.1.x/core/install/upgrades.sql	(.../upgrades.sql)	(revision 13811)
+++ branches/5.1.x/core/install/upgrades.sql	(.../upgrades.sql)	(revision 13816)
@@ -1925,3 +1925,7 @@
 
 # ===== v 5.1.0 =====
 UPDATE Events SET Headers = NULL WHERE Headers = '';
+
+UPDATE Events
+SET MessageType = 'text'
+WHERE Event = 'FORM.SUBMISSION.REPLY.TO.USER';