I helped my previous laboratory to move the server, and upgrade to Debian 4.0r0 with Apache 2. Upgrading to Apache 2 is somewhat tedious, because a lot of configuration need to be changed. Below are two notes:

Virtual Host

The correct way of doing in Apache 2 is:

NameVirtualHost *
<VirtualHost *>
    ServerName www.site_one.net
    # Something else
<VirtualHost *>
    ServerName www.site_two.net
    # Something else

Note about the asterisk used. Only those labeled on NameVirtualHost can be used in VirtualHost tag. These virtual host configuration is stored in /etc/apache2/sites-available and a symlink is created in /etc/apache2/sites-enabled. Their use is self-explanatory.

User Dir

The Debian’s version of configuration file has some problem on the external modules. Search for modes-available and you will see these:

Include /etc/apache2/mods-enabled/*.load
Include /etc/apache2/mods-enabled/*.conf

which means you should create symlinks of both .load and .conf files on the mods-enabled directory. Actually you should have

Include /etc/apache2/mods-available/*.conf

However, when you do that, remember to correct some .conf files as they ain’t enclosed in a pair of IfModule tag.