Apache2 subdomains (different ports) redirection

httpd.conf

### from http://serverfault.com/questions/195611/how-do-i-redirect-subdomains-to-a-different-port-on-the-same-server

NameVirtualHost *:80

<VirtualHost *>
    ServerAdmin [email protected]
    ServerName dev.mydomain.com
    ProxyPreserveHost On

    # setup the proxy
    <Proxy *>
        Order allow,deny
        Allow from all
    </Proxy>
    ProxyPass / http://localhost:8888/
    ProxyPassReverse / http://localhost:8888/
</VirtualHost>

###---------------------------------

NameVirtualHost *:80

<VirtualHost *:80>
    ServerName dev.mydomain.com
    redirect / http://mydomain.com:8080/
</VirtualHost>

###---------------------------------

ProxyPreserveHost On
ProxyPass / http://example.com:8080/
ProxyPassReverse / http://example:8080/

###---------------------------------

RewriteEngine on
RewriteCond %{HTTP_HOST} ^dev\.example\.com$ [NC]        
RewriteRule ^(.*)$ http://example.com:8080$1 [R=301]