Accesability law

Just want to know really…

A client of mine said that a law has been passed recently saying that all content on the web must now be accesable to people who are visually impaired. Or else the designer may be liable and get sued!

While I agree that it would be wonderful for everyone to be able to experience the web to the fullest, this does not seem practical or even possible given the available technology.

Is what he says true? I have been unable to find anything stating that all websites MUST abide by this ‘law’ or even that this ‘law’ even exists, so I am somewhat skeptical.

Can anyone shed any light on this?