Multiple currency problem : "You need to expand the transaction in order to modify its exchange rates."

[Gregor Vercaigne]

Hi,

I use version 1.8.9 and Euro as default currency.

What I want to do is the following:

A broker account in Euro and one in dollar.
Each broker account then has a number of stock child accounts in that
currency.

When I want to balance the "Intial purchase" of the Euro stocks in 
"Equity:Opening balances (Euro)" there is no problem for the euro
stocks.

But when I try to do the same for the dollar stocks, I can only record
1, the next "Intial purchase" doesn't. Exchange rates are set up and
commodities also. 

When I try to fill in the missing transfer in the 
"Equity:Opening balance dollar" account, I get the following error:  

"You need to expand the transaction in order to modify its exchange
rates."

Thx for your help,

Greg