diff --git a/dba/patches/1.1.11.sql b/dba/patches/1.1.11.sql
new file mode 100644
index 00000000..60a55e55
--- /dev/null
+++ b/dba/patches/1.1.11.sql
@@ -0,0 +1,16 @@
+
+-- Sort out accessing calendar entries.
+
+BEGIN;
+SELECT check_db_revision(1,1,10);
+
+ALTER TABLE calendar_item DROP CONSTRAINT "$1";
+ALTER TABLE calendar_item ADD CONSTRAINT "$1" FOREIGN KEY (user_no) REFERENCES usr(user_no) ON UPDATE CASCADE ON DELETE CASCADE DEFERRABLE;
+ 
+ALTER TABLE collection DROP CONSTRAINT "$1";
+ALTER TABLE collection ADD CONSTRAINT "$1" FOREIGN KEY (user_no) REFERENCES usr(user_no) ON UPDATE CASCADE ON DELETE CASCADE DEFERRABLE;
+
+SELECT new_db_revision(1,1,11, 'November' );
+COMMIT;
+ROLLBACK;
+
diff --git a/dba/rscds.sql b/dba/rscds.sql
index 33382bfa..ce52431a 100644
--- a/dba/rscds.sql
+++ b/dba/rscds.sql
@@ -7,7 +7,7 @@
 
 -- The main event.  Where we store the things the calendar throws at us.
 CREATE TABLE caldav_data (
-  user_no INT references usr(user_no),
+  user_no INT references usr(user_no) ON UPDATE CASCADE ON DELETE CASCADE DEFERRABLE,
   dav_name TEXT,
   dav_etag TEXT,
   created TIMESTAMP WITH TIME ZONE,
@@ -69,7 +69,7 @@ GRANT SELECT,INSERT,UPDATE,DELETE ON calendar_item TO general;
 
 -- Something that can look like a filesystem hierarchy where we store stuff
 CREATE TABLE collection (
-  user_no INT references usr(user_no),
+  user_no INT references usr(user_no) ON UPDATE CASCADE ON DELETE CASCADE DEFERRABLE,
   parent_container TEXT,
   dav_name TEXT,
   dav_etag TEXT,
@@ -142,4 +142,4 @@ CREATE TABLE freebusy_ticket (
 
 GRANT INSERT,SELECT,UPDATE,DELETE ON TABLE freebusy_ticket TO general;
 
-SELECT new_db_revision(1,1,10, 'October' );
+SELECT new_db_revision(1,1,11, 'November' );