For some confederations (UEFA) this is true. For CONCACAF (USA, Canada, Mexico, etc) It will be determined by an Olympic qualifying tournament in Mexico February 2-12, 2004. concacaf.com has the prelimaries and the schedules for both men and women.
Qualifying for the 2004 Olympics If Sweden loses the opening match today against Brazil, Norway will qualify for the Olympics with a victory in their match against the U.S. However, in the unlikely event that Sweden and Norway both win today, Norway would play the winner of the Germany - Russia match in the semis and the winner of that match would qualify for the Olympics. If Sweden were to also win in the semis then they would get the final UEFA spot in the Olympics.