LdapCalendarResource res = null;
    public CalendarResource getCalendarResourceByForeignPrincipal(            String foreignPrincipal)    throws ServiceException {        LdapCalendarResource res = null;        foreignPrincipal = LdapUtil.escapeSearchFilterArg(foreignPrincipal);        LdapCalendarResource resource =            (LdapCalendarResource) getAccountByQuery(                "",                "(&(zimbraForeignPrincipal=" + foreignPrincipal + ")" +                FILTER_CALENDAR_RESOURCE_OBJECTCLASS + ")",                null);        sAccountCache.put(resource);        return resource;    }