Just tested whiterussian RC2, both on a WRT54G v2.2 and motorola WR850G v2:
The nvram variables wl0_country and wl0_country_code seem to be completely ignored.
The default is:
wl0_country=USA
wl0_country_code=US
I changed it to:
wl0_country=SPAIN
wl0_country_code=ES
The output of "wl country" is:
USA/UNITED STATES
I also tried other combinations of wl0_country/wl0_country_code to no avail.
The only way I could find to set the country code correctly is:
wl down
wl country ES
wl up