function timeLocked(address _spender)
    public
    constant
    returns (bool)
    {
        if (releaseTimes[_spender] == 0) {
            return false;
        }

        
        var _time = timeMode == TimeMode.Timestamp ? block.timestamp : block.number;
        if (releaseTimes[_spender] <= _time) {
            delete releaseTimes[_spender];
            return false;
        }

        return true;
    }