A piece has been circulating on right-wing websites and message boards attacking John Kerry's war record. The piece is mainly built from an article in the renown New York Sun. The piece includes some supposed criticisms of Kerry by Admiral Elmo Zumwalt. Here are some factual responses:
http://www.snopes.com/politics/kerry/service.asp The snopes website specializes in exposing lies on internet message board/email urban legends. You might note in this response that the Bronze Star nomination for John Kerry was personally signed by Admiral Zumwalt.
The supposed quote from Zumwalt about Kerry was reported by a former Assistant Secretary of Defense, W. Scott Thompson, who was the only person who heard it. He apparently was a Reagan Administration appointee and works for an institute that is closely connected to the CIA and receives funding from the ultra-conservative Scaife Foundation. Zumwalt is dead, so there is no way to confirm it.
Here's a detailed article on Kerry's war record from the Guardian, which is the most respected newspaper in Britain. This article refers to the Zumwalt quote as a joke that Zumwalt made because Kerry was being too aggressive about chasing the enemy.
http://www.guardian.co.uk/uselections2004/story/0,13918,1160084,00.html