Index: branches/5.3.x/core/install/upgrades.sql
===================================================================
diff -u -N -r16213 -r16319
--- branches/5.3.x/core/install/upgrades.sql	(.../upgrades.sql)	(revision 16213)
+++ branches/5.3.x/core/install/upgrades.sql	(.../upgrades.sql)	(revision 16319)
@@ -3026,3 +3026,10 @@
 UPDATE Modules
 SET ClassNamespace = 'InPortal\\Core'
 WHERE `Name` IN ('Core', 'In-Portal');
+
+UPDATE EmailTemplates
+SET
+	l1_Subject = REPLACE(l1_Subject, '<inp2:u_', '<inp2:'),
+	l1_HtmlBody = REPLACE(l1_HtmlBody, '<inp2:u_', '<inp2:'),
+	l1_PlainTextBody = REPLACE(l1_PlainTextBody, '<inp2:u_', '<inp2:')
+WHERE TemplateName LIKE 'USER.MEMBERSHIP%';