Zero amount in document currency

Hi,

I'm looking for if I could fill a zero amount in WRBTR field, in document currency.

My customer would like to fill a zero amount in GBP currency in company with a local currency in EUR. So he would like to entry a zero amount in document currency and 0.01 EUR in amount in local currency. But when I try to fill the zero amount, SAP change the amount with 0.01. Thus it's not correct for him.

May I change the customizing to force SAP and accept my value ?

Thank for any helps.

Gilles.