diff --git a/docs/changelog/7.x.x.txt b/docs/changelog/7.x.x.txt
index 99992683c..7a929ca5d 100644
--- a/docs/changelog/7.x.x.txt
+++ b/docs/changelog/7.x.x.txt
@@ -3,6 +3,7 @@
  - Config file bugs fixed, see gotcha.txt for details.
  - Added export to context menu in asset manager
  - fix: XHTML 1.0 strict, FileUploadControl.js, resizable textarea
+ - fix: undefined activity
  - Polls now use JSON instead of Storable to serialize graph config
 
 
diff --git a/docs/upgrades/upgrade_7.4.2-7.4.3.pl b/docs/upgrades/upgrade_7.4.2-7.4.3.pl
index c3e31344a..52b55d594 100644
--- a/docs/upgrades/upgrade_7.4.2-7.4.3.pl
+++ b/docs/upgrades/upgrade_7.4.2-7.4.3.pl
@@ -12,7 +12,9 @@ use lib "../../lib";
 use strict;
 use Getopt::Long;
 use WebGUI::Session;
-
+use WebGUI::Workflow::Cron;
+use WebGUI::Asset;
+use WebGUI::Utility;
 
 my $toVersion = "7.4.3"; # make this match what version you're going to
 my $quiet; # this line required
@@ -22,16 +24,32 @@ my $session = start(); # this line required
 
 # upgrade functions go here
 reserializePollGraphConfigs($session);
+fixCsMailWorkflow($session);
 
 finish($session); # this line required
 
 
-##-------------------------------------------------
-#sub exampleFunction {
-#	my $session = shift;
-#	print "\tWe're doing some stuff here that you should know about.\n" unless ($quiet);
-#	# and here's our code
-#}
+#-------------------------------------------------
+sub fixCsMailWorkflow {
+	my $session = shift;
+	print "\tFixing CS Mail workflows and crons.\n" unless ($quiet);
+    # get valid crons
+    my $collaborations = $session->db->read("select assetId from asset where className like 'WebGUI::Asset::Wobject::Collaboration%'");
+    my @cronIds = ();
+    while (my ($id) = $collaborations->array) {
+        my $cs = WebGUI::Asset->newByDynamicClass($session, $id);
+        if (defined $cs) {
+            push(@cronIds, $cs->get("getMailCronId"));
+        }
+    }
+    # delete invalid crons
+    for my $task (@{WebGUI::Workflow::Cron->getAllTasks($session)}) {
+        next unless ($task->get("className") =~ m/WebGUI::Asset::Wobject::Collaboration/);
+        unless (isIn($task->getId, @cronIds)) {
+            $task->delete;
+        }
+    }
+}
 
 #-------------------------------------------------
 sub reserializePollGraphConfigs {
diff --git a/lib/WebGUI/Asset/Wobject/Collaboration.pm b/lib/WebGUI/Asset/Wobject/Collaboration.pm
index 56f2af70f..c71bf3f31 100644
--- a/lib/WebGUI/Asset/Wobject/Collaboration.pm
+++ b/lib/WebGUI/Asset/Wobject/Collaboration.pm
@@ -324,7 +324,7 @@ sub commit {
 		$cron = WebGUI::Workflow::Cron->create($self->session, {
 			title=>$self->getTitle." ".$i18n->get("mail"),
 			minuteOfHour=>"*/".($self->get("getMailInterval")/60),
-			className=>"WebGUI::Asset::Wobject::Collaboration",
+			className=>(ref $self),
 			methodName=>"new",
 			parameters=>$self->getId,
 			workflowId=>"csworkflow000000000001"