As you may read or see Yahoo! was finally back to fight with lobby spam bots a while ago . But that was a bad captcha (confirmation codes) which using six hard type (bold) letters to us to verify but i was having very hard times to read them on my 1920×1200 screen resulation , especially the bold fonts. That was a bad confirmation code for humans but it was no problem for the spam bots to solve so it didn’t effect them.
Now Yahoo! change the old one and have a new confirmation code .It has only 4 letters which can be read easier. If you still unable to read them Yahoo! add the audio code which is a good move.Of course this update means they got that humans can’t read the old confirmation code and it didn’t stop the bots.Oh and i know this new code will not stop bots also.