Mac OS X 10.5.X Leopard on iBook G4 800Mhz

Hi to all the people who want to install Mac OS X 10.5.X Leopard on their iBooks g4 with 800mhz or slower cpu's, i will talk about how to hack the installation, to drop the system requirements for such systems. First of all you need to find Mac OS X 10.5.X installation media DVD-SL (DVD Single Layer), it can be found using google ;-) (THIS IS ILLEGAL!!!) by the way i used 10.5.6 version. Burn this DVD image to disc, insert it to your mac then reboot.



After start up sound press and hold "c" button, until reading from DVD starts. After installation start up, you will be pointed for language selection, after that you will be informed about insufficient system requirements "Cannot Install On This Computer" Press OK and open terminal from Menu > Utilities. Make sure you have USB stick with 128mb or more memory formatted to FAT.

Do the following steps:

Copy OSInstall.mpkg to USB Stick:
# cp /Volumes/<MAC OS X Install DVD>/System/Installation/Packages/OSInstall.mpkg /Volumes/<USB STICK>/ORIG_OSInstall.mpkg

Unpack OSInstall archive with xar:

# cd /Volumes/<USB STICK>/ && xar -xvf ./ORIG_OSInstall.mpkg

It will create directory Resources and Distribution file, you need to make a directory and put these two in it.

# mkdir OSInstall

# mv Distribution OSInstall/

# mv Resources OSInstall/

# cd OSInstall

You need to modify Distribution file, if you have Tiger or any other OSX installed you can use TextEdit to do this, or you can eject USB Stick and modify this file on other machine, then put it back. If you have OSX on computer already installed then launch TextEdit and edit it:

# /Volumes/<Macintosh HD>/Applications/Textedit.app/Contents/MacOS/TextEdit Distribution

Search for "function installCheckScript()" and delete all contents except "return true;" from it, the function should look like this:

function installCheckScript() {
return true;
}

Save and quit TextEdit. Then run this to create your own hacked installation package:

# xar -cvf ../myinstall.mpkg .

Create symlinks for all of the base OS install packages on your USB STICK by pointing to the packages on the boot volume:

# cd ..
# ln -s /System/Installation/Packages/* .

Copy the rc.install file to /private/var/tmp

# cp /etc/rc.install /private/var/tmp/my.install

Open /private/var/tmp/my.install with same TextEdit (or you can do this on other computer as i said before):

# /Volumes/<Macintosh HD>/Applications/Textedit.app/Contents/MacOS/TextEdit private/var/tmp/my.install

Search for line "INSTALL_PKG=/System/Installation/Packages/OSInstall.mpkg" and change it to "INSTALL_PKG=/private/var/tmp/myinstall.mpkg" then save and exit.

Create a symlink to point to /private/var/tmp from the USB STICK for your install package:

# ln -s /Volumes/<USB STICK>/myinstall.mpkg /private/var/tmp/myinstall.mpkg

Re-define shell variable of the installer package:

# export INSTALL_PKG="/Volumes/<USB STICK>/myinstall.mpkg"

Remove the installer pid file:

# rm /private/var/run/installer

Finally launch the installer:

# /private/var/tmp/my.install

Please don't remove USB STICK until installation is finished. If anything goes wrong please Re-Read this text carefully, and post a comment if you have some questions.

BTW, <Macintosh HD> means volume name of you preinstalled OSX volume and <USB STICK> of your usb flash stick FAT volume name.

Enjoy! ;-)