[GNC] Stock bought in CAD pays dividends in USD

[rsbrux]

I have a Canadian stock which was purchased on the Toronto Stock
Exchange with Canadian dollars (CAD). However, much to my surprise, the
dividends are being paid out in USD. I followed the usual instructions
when creating the stock account in GC to allow me to buy the stock in
CAD (with funds from a CAD denominated current account). The result is
that the amounts I enter into GC for dividends are being recorded as
CAD (C$), even though I have selected USD accounts for the dividend
income, the deducted taxes and the net payout.
How can I properly record the USD dividends in GnuCash for a stock
purchased in CAD?