How to partition one for Leopard and anoter partition for Tiger?

[mayachoy]

I had a external HDD i want to partition it into two OS one for Leopard and another for Tiger. How to do so? If it's not possible how to do the partition on Mac system. Thank you.:)

[Jaysen]

Not being leopard user I am not sure how to do this from leopard, but to do this in tiger...

Open Disk utility.
Partition the disk into 2 slices. DO NOT FORMAT THEM. I recommend naming them so you can id them easily.
Put the install media into the dvd drive and reboot
When going through the installer make sure to select the partition for the OS you are installing. You should see the internal drive, and the 2 partitions of the external.
Repeat for second OS.

Again, I do this with tiger, so there may be extra seeps needed for leopard that I don't know about.