Older, diy howto: You need a wireless access point and a router that runs 
Linux. The router should have a webserver too. I used my own access point and 
the Debian server which acts as a router.

First, get the files corresponding to your phone from 
http://spritesmods.com/vpx500/philips . Move 
them to your webserver in such a way that they can be downloaded at 
http://your_routers_ip/philips/VP6500/ . Don't extract the hack.tgz, just 
move it! The VP5500 uses a directory named vp5500 (no caps!), so you may 
need to account for the change. Check your webservers logs for more info. 

Now, make sure to configure your router to route all traffic to 
vpcm-001.cust.kpn.net, port 80, to the address. What should happen is 
that when you go to http://vpcm-001.cust.kpn.net/philips/VP6500/ from your 
WLAN, you end up at the directory on your routers website. Redirection can 
be done with both dns and with an iptables-rule, by the way, please figure 
that part out yourself. While you're at it, also try to redirect ntp.xs4all.nl,
port 37, to your local machine and run this command on the router:

echo -ne '\xCF\x21\xC9\x7F' | nc -q 1 -l -p 37

(nc may be called netcat on some distro's)

Now, start or reboot the phone and let it sit for a couple of minutes 
(max 10) if you did the the ntp.xs4all.nl redirection. If you didn't, you 
have to wait till 02.05AM for the device to do an upgrade, unfortunately. 
Either way, the phone should do a software-update eventually and then reboot.