Mine

NameVirtualHost *:80

<VirtualHost  *:80>
DocumentRoot /var/www/html/
ServerName www.sudoku-solver.net
</VirtualHost>


<VirtualHost *:80>
DocumentRoot /var/www/html/memgame/
ServerName  www.photographicmemorygame.com
</VirtualHost>


Options +FollowSymLinks
RewriteEngine On
RewriteCond %{HTTP_HOST} ^sudoku-solver\.net$ [NC]
RewriteRule ^(.*)$ http://www.sudoku-solver.net$1 [R=301,L]