diff --git a/mod/workshop/db/upgrade.php b/mod/workshop/db/upgrade.php
index 3b2dd18fe1eeb..b5ab5467c03e2 100644
--- a/mod/workshop/db/upgrade.php
+++ b/mod/workshop/db/upgrade.php
@@ -322,5 +322,42 @@ function xmldb_workshop_upgrade($oldversion) {
     // Moodle v2.2.0 release upgrade line
     // Put any upgrade step following this
 
+    /**
+     * Remove all workshop calendar events
+     */
+    if ($oldversion < 2011112901) {
+        require_once($CFG->dirroot . '/calendar/lib.php');
+        $events = $DB->get_records('event', array('modulename' => 'workshop'));
+        foreach ($events as $event) {
+            $event = calendar_event::load($event);
+            $event->delete();
+        }
+        upgrade_mod_savepoint(true, 2011112901, 'workshop');
+    }
+
+    /**
+     * Recreate all workshop calendar events
+     */
+    if ($oldversion < 2011112902) {
+        require_once(dirname(dirname(__FILE__)) . '/lib.php');
+
+        $sql = "SELECT w.id, w.course, w.name, w.intro, w.introformat, w.submissionstart,
+                       w.submissionend, w.assessmentstart, w.assessmentend,
+                       cm.id AS cmid
+                  FROM {workshop} w
+                  JOIN {modules} m ON m.name = 'workshop'
+                  JOIN {course_modules} cm ON (cm.module = m.id AND cm.course = w.course AND cm.instance = w.id)";
+
+        $rs = $DB->get_recordset_sql($sql);
+
+        foreach ($rs as $workshop) {
+            $cmid = $workshop->cmid;
+            unset($workshop->cmid);
+            workshop_calendar_update($workshop, $cmid);
+        }
+        $rs->close();
+        upgrade_mod_savepoint(true, 2011112902, 'workshop');
+    }
+
     return true;
 }
diff --git a/mod/workshop/version.php b/mod/workshop/version.php
index 9fd8a8cdab3a0..f21fe8f4ac235 100644
--- a/mod/workshop/version.php
+++ b/mod/workshop/version.php
@@ -25,7 +25,7 @@
 
 defined('MOODLE_INTERNAL') || die();
 
-$module->version   = 2011112900;       // The current module version (Date: YYYYMMDDXX)
+$module->version   = 2011112902;       // The current module version (Date: YYYYMMDDXX)
 $module->requires  = 2011112900;       // Requires this Moodle version
 $module->component = 'mod_workshop';   // Full name of the plugin (used for diagnostics)
 $module->cron      = 0;