pingable_mbrs.removeAllElements();
pingable_mbrs.clear();
    void unsuspect(Address mbr) {        bcast_task.removeSuspectedMember(mbr);        pingable_mbrs.removeAllElements();        pingable_mbrs.addAll(members);        pingable_mbrs.removeAll(bcast_task.getSuspectedMembers());        ping_dest=(Address)getPingDest(pingable_mbrs);    }