--- a/calendar/providers/wcap/calWcapCalendar.js
+++ b/calendar/providers/wcap/calWcapCalendar.js
@@ -150,16 +150,19 @@ calWcapCalendar.prototype = {
                     path.substring(start, end == -1 ? path.length : end));
             }
         }
         return this.uri;
     },
 
     getProperty: function calWcapCalendar_getProperty(aName) {
         switch (aName) {
+            case "cache.supported":
+                return false; // TODO Sorry, but until we implement the new
+                              // calIChangeLog interfaces, we must disable the cache for wcap.
             case "timezones.provider":
                 return ((this.m_session && this.session.isLoggedIn) ? this.session : null);
             case "organizerId":
                 return this.ownerId;
             case "organizerCN":
                 return this.getCalendarProperties("X-S1CS-CALPROPS-COMMON-NAME");
             case "itip.disableRevisionChecks":
                 return true;