diff -ru evolution-exchange-2.28.1/calendar/e-cal-backend-exchange-calendar.c evolution-exchange-2.28.1-bug115913/calendar/e-cal-backend-exchange-calendar.c
--- evolution-exchange-2.28.1/calendar/e-cal-backend-exchange-calendar.c	2009-10-17 17:46:28.000000000 -0600
+++ evolution-exchange-2.28.1-bug115913/calendar/e-cal-backend-exchange-calendar.c	2009-11-09 10:01:09.000000000 -0700
@@ -836,6 +836,22 @@
 	cbdata->vcal_comp = e_cal_util_new_top_level ();
 	cbdata->cal = cal;
 
+	/* Though OWA produces "CLASS:" (which we map to
+	 * "CLASS:PUBLIC" above), it will accept "CLASS:PUBLIC".
+	 * However, some other exchange clients, notably Windows
+	 * Mobile Outlook, don't work unless we map "CLASS:PUBLIC"
+	 * back to "CLASS:". For details, see
+	 * https://bugs.launchpad.net/ubuntu/+source/evolution-exchange/+bug/115913
+	 */
+	icalprop = icalcomponent_get_first_property (icalcomp, ICAL_CLASS_PROPERTY);
+	if (icalprop && !g_ascii_strcasecmp (icalproperty_get_value_as_string (icalprop), icalproperty_enum_to_string (ICAL_CLASS_PUBLIC)))
+	{
+		icalcomponent_remove_property (icalcomp, icalprop);
+		icalproperty_free (icalprop);
+		icalprop = icalproperty_new_class (ICAL_CLASS_NONE);
+		icalcomponent_add_property (icalcomp, icalprop);
+	}
+
 	/* Remove X parameters from properties */
 	/* This is specifically for X-EVOLUTION-END-DATE,
 	   but removing anything else is probably ok too */
