The primary problem with installing operating systems on a mac is the partitioning system. Intel macs use the new GPT method to partition drives. This is supported by OSX (obviously) and linux. However windows can only be installed on a machine with a legacy (MBR) based partitioning system. In order to overcome this, bootcamp uses both systems, and herein lies the difficulty in triple booting. Currently there is no partitioning software available apart from diskutil (included with OSX 10.4.6) that can create dual gpt/mbr partition system drives. Current GPT based partitioners (eg parted) wipe the MBR partion, whereas current MBR partitioners (fdisk/partion magic) can't edit GPT.

In other words we have to manually partition the drive using diskutil in order to get the necessary partition structure for triple booting. However it gets worse. MBR only supports 4 primary partitions and GPT does not support extended partitions. Combining these two limitations means that a dual partition system disk can have a maximum of 4 primary partitions. In addition, apple reserves the first primary partition for their bootloader. That leaves us with only three partitions to play with, one for each OS. Hence, we cannot have a linux swap partition, instead we must create a swapfile. Also, for some reason bootcamp expects the windows "c:" drive to be the last partition present the drive. If it isn't windows setup will crash with a "cannot find hall.dll" error after the first reboot.

Finally, it is best to stick with the advice given by Apple and format the windows partition as FAT32. If you use NTFS there is a possibility the GPT/MBR partition tables will no longer agree. However if you do decide to stick with FAT32 your windows partition cannot be greater than 32GB.