first you try this short setting..
<VirtualHost *>
ServerName www.myDomain.com
DocumentRoot /www/myDomainRoot
</VirtualHost>
/* then after detailed configuration for that */
/etc/apache2/sites-available/default
<VirtualHost <yourIP address>:<PortNo>>
ServerAdmin webmaster@localhost
ServerName application.mymachine #or whatever
DocumentRoot /var/www
<Directory />
Options FollowSymLinks
AllowOverride None
</Directory>
<Directory /var/www/>
Options Indexes FollowSymLinks MultiViews
AllowOverride None
Order allow,deny
allow from all
</Directory>
</VirtualHost>