This game note is from the writeup about the US U20's playing Brazil last Saturday. Game Notes: The U.S. wore blue jerseys with white shorts and white socks, while Brazil wore their traditional yellow-blue-white strip … Brazil kicked off to start the game … Under tournament rules, Clark will not be suspended for the USA’s next match … Players are only suspended for straight red cards or three cautions across the entire tournament … Steve Cronin was forced to switch jerseys (from grey to black) prior to the game, as the Brazilian ‘keeper was wearing the same goalkeeper shirt … Devin Barclay wore the captain’s armband for the U.S. ... Steve Cronin is the only U.S. player to play every minute of all six international matches in 2002. I was curious about the reference to the US keeper, Steve Cronin, having to change his jersey because it was the same as Brazil's keeper. Why would it matter if both keepers wore the same jersey as long as they're distinct from the two teams? Full text of article here: http://www.soccer365.com/US_home/National_Teams/page_22_38038.shtml
The LOTG actually specify that each keeper wear a shirt of a different color then that of his team mates and the other keeper. This is a newer addition to laws. It came about after Peter Schmichel made a habbit of going into the opposing team's penalty area late in games to challenge for a header on corners. It's an easy way for referees to clearly distinguish between the keepers in this situation.