Currencies - rate


In currencies > Rate field I am able to set exchange rate of 1eur = 0.289Lt

Is it posible to set more then 3 decimals? For example 0.28922?

Just checked demo and max allowed in latest cart are 5 decimals, how can I do this with earlier cart?

Euro Rate is 1.28000

2.1.4 allows set only 1.280