HOWTO install Linux on a Mac Intel

1. Resize the MacOS partition using `BootCamp Assistant` creating another partition (this will be your future root partition). 
   
2. Download and install rEFIt. 
   
3. Reboot your Mac with the Linux bootable CD. 
   
4. Create the ext3 partition and set it `bootable`.
   
5. Reboot the machine and use the rEFIt tool to sync the GPT/MBR table.
   
6. Reboot the machine with the Linux bootable CD and complete the installation process. 
   
7. Install LILO into the same Linux partition (NOT into the MBR) instead of GRUB (grub doesn't support the ext3 with 256inode yet) 
   

Now your dualboot is ready. If you want to create a swap partition create a file into the Linux partition with dd and modify your /etc/fstab 

This is the output of diskutil list on MacOS X

# diskutil list

/dev/disk0

#:         TYPE NAME              SIZE       IDENTIFIER

0:   GUID_partition_scheme      *149.1 Gi       disk0

1:            EFI                200.0 Mi      disk0s1

2:   Apple_HFS Macintosh HD      127.9 Gi      disk0s2

3:            EFI                 20.9 Gi      disk0s3

#