you'd have to hack your system and use a chip.....i did that on my PS1 awhile back....lemme copy/paste the FAQs on chipping....
PS2 MODS
What is a Mod or Mod Chip ?
When installed in your gaming system, a PS2 or XBox, a mod chip will allow you to play imported games as well as backups of your own games made on CD-R or DVD-R Media.
Can I have the PS2 chipped to play Import Games?
Some web sites sell chips or Mods for the PS2 but it is your decision. Mods will almost certainly invalid your Console Warranty, and it is illegal. As a Mod will also modify the reaction of the Console you may get incompatibilities and unusual reactions.
Is Modding illegal ?
A Chip is a device which circumvents copyright protection. The UK Copyrights, Designs and Patents Act deals with such devices as a civil offence.
Does Modding invalid your Console Warranty ?
Almost certainly yes.
Why would I need a mod chip to play imports and backups?
The PlayStation 2 checks the country code on the PS2 CD Roms / DVDs before it allows the game to start. If the country code on the disc does not match that of your PlayStation 2, it will not allow you to play the game. Similarly, the console checks to make sure you have inserted an original disc.
Does a Mod Chip work on all PlayStation 2 models?
There are chips that will work on all PlayStation 2 models but some will only work with certain versions of the PS2.
Why are there so many different kinds of mod chips?
As Sony continue to enhance their consoles so Mod chip developers meet the demand with new and more sophisticated chips.
Is it hard to install a Mod Chip?
To install a Mod Chip you need to know how to solder. The typical installation time quoted is 30-60 minutes - from unscrewing the first screw to putting the last screw back in. The installation requires you to solder from 4 to 23 wires to your PlayStation 2, depending on the version mod chip. In any event safety and competence with soldering and electrics will be necessary and some expert guidance.
Are there other solutions for playing my backups and imports?
Yes there are external Neo Keys and several other plug-n-play devices such as the combination of the Fliptop shell and the Swap Magic disc set.
Things you should check before you consider a Mod.
If you are still determined to Mod your Console you will need to find out what kind of PS2 Mod chips are compatible with your system. For this you will need to determine what version of PS2 you have . This is indicated on the information plate on the rear of the PS2 - detailing Model; Region (PAL/ NTSC); Serial and maybe Date.
here's some info on installation if you really feel construsctive....
http://www.expert-guides.com/library/ps2_install.asp?adid=40350
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