Just upgraded my T42 IBM to Feisty Fawn and everything except the font rendering looks great.
To enable smooth fonts, put the following in a file in your /home directory named .fonts.conf:

<?xml version=”1.0″?>
<!DOCTYPE fontconfig SYSTEM “fonts.dtd”>
<fontconfig>
<match target=”font”>
<edit name=”autohint” mode=”assign”>
<bool>true </bool>
</edit>
</match>
</fontconfig>
Then, log out and log back in again and the fonts will be very smooth.

Also, I followed these instructions to get Beryl up and running, which works flawlessly.