Yahoo! are Testing a new
Chat Room Verification system

This how it will look in Yazak

The link above when you click on it bring up this page

Enter the correct letters you will then get this page

And be put into the Chat Room

Here are some more messages that come up if you continue typing

Yahoo are using
CAPTCHA: Telling Humans and Computers Apart Automatically
See link www.captcha.net

See also www.cmu.edu/index.shtml