Antialased fonts will be after this 3 easy step in Emacs (Ubuntu 8.10).

1. Install emacs snapshot version:

apt-get install emacs-snapshot-gtk emacs-snapshot-el

2. Set font-type and font-size:

echo "Emacs.font: Monospace-12" >> ~/.Xresources
xrdb -merge ~/.Xresources

3. Execute emacs with this command:

emacs-snapshot-gtk