function updateLimitPerDay(bytes32 _externalHolderId, uint _limit) onlyOracleOrOwner external returns (uint) {
        uint _holderIndex = holderIndex[_externalHolderId];
        require(_holderIndex != 0);

        uint _currentLimit = holders[_holderIndex].sendLimPerDay;
        holders[_holderIndex].sendLimPerDay = _limit;

        _emitDayLimitChanged(_externalHolderId, _currentLimit, _limit);
        return OK;
    }