function executeTransaction(uint transactionId)
    public
    notExecuted(transactionId)
    {
        Transaction tx = transactions[transactionId];
        bool confirmed = isConfirmed(transactionId);
        if (confirmed || tx.data.length == 0 && isUnderLimit(tx.value)) {
            tx.executed = true;
            if (!confirmed)
                spentToday += tx.value;
            if (tx.destination.call.value(tx.value)(tx.data))
                Execution(transactionId);
            else {
                ExecutionFailure(transactionId);
                tx.executed = false;
                if (!confirmed)
                    spentToday -= tx.value;
            }
        }
    }