Wrong Country added to customers address

[FrankMaly]

My webshop is hosted in Germany.

I used https://www.paypal.com/cgi-bin/webscr

with parameters of 

&cmd=_xclick&business=XXXXXX&item_name=www.reimo.com.au&encoding=utf-8&closewin=J&waehrung=AUD&loginlanguage=US&bn=AU

When a customer checks out using PayPal, Germany is added as the Country (to the customers address).

How do I add Australia to the transaction, and not some default country (ie Germany)?

Any assistance would be much appreciated.

Thanks