VHOSTS and multiple IP's (no replies)

Hi guys

I have some projects in work and i already installed WAMP server. Also i added some IP's aliases on my network card. My ip's are from C class... such as 192.168.100.x to 192.168.100.y
I want to have a virtual host for every project bind to an IP... something like that: project1 -> vhost1-> ip1 -> port 80

For example:

<VirtualHost 192.168.100.10:80>
ServerName project1
ServerAlias project1
DocumentRoot "d:/projects/project1"
<Directory "d:/projects/project1/">
Options +Indexes +Includes +FollowSymLinks +MultiViews
AllowOverride All
Require local
</Directory>
</VirtualHost>

When i defined my virtual hosts using wamp my hosts file was overwritten. Can you add an option to be backuped, before to be modified? Or just simply, to add the new definitions at the end of the file?

Best regards
Alex