fixed: iCal feeds don't update properly when events are changed

docs/changelog/7.x.x.txt

@@ -22,6 +22,7 @@
  - fixed: international characters corrupted in titles
  - fixed: Users without karma can transfer karma by rating posts
  - fixed: gateway macro not usable in links in rich editor
+ - fixed: iCal feeds don't update properly when events are changed
 
 7.5.9
  - fixed: Collaboration System attachments follow site's max size instead of CS's

docs/upgrades/upgrade_7.5.9-7.5.10.pl

@@ -24,6 +24,7 @@ my $session = start(); # this line required
 
 privatizeVisitor($session);
 ucfirstThingyFieldTypes($session);
+addEventSequenceNumber($session);
 
 finish($session); # this line required
 
@@ -36,6 +37,15 @@ finish($session); # this line required
 #    print "DONE!\n" unless $quiet;
 #}
 
+#----------------------------------------------------------------------------
+sub addEventSequenceNumber {
+    my $session = shift;
+    print "\tAdding iCal sequence number to events... " unless $quiet;
+    $session->db->write('ALTER TABLE Event ADD COLUMN iCalSequenceNumber int');
+    $session->db->write('UPDATE Event SET iCalSequenceNumber=0');
+    print "Done.\n" unless $quiet;
+}
+
 #----------------------------------------------------------------------------
 sub privatizeVisitor {
     my $session = shift;