Adding virtual directory to apache on ubuntu 8.10

To add virtual directory to apache (Zend Core) on ubuntu 8.10, is different from FC somewhere. the step is the following:
1 makdir

mkdir /home/edwin/Documents/Wiki

2 add setting to the http.conf

alias /Wiki/ "/home/edwin/Documents/Wiki/"

<Directory "/home/edwin/Documents/Wiki">
Options indexes FollowSymLinks
AllowOverride none
Order allow,deny
Allow from all
</Directory>

3 restart apache