Installing Leopard on Firewire External Drive for iBook G4

[djab]

Ok im trying to install Mac OS X 10.5 on to an external drive. I want to run Leopard off of an External Hard Drive which will connect via Firewire of USB 2.0. I have booted up using the install DVD that i bought a couple years ago to upgrade from Tiger. However each time i install i get an error saying that it cannot be installed. It allows me to start the install and is almost complete before i get this error. I have it partitioned using the Apple Partition Map so i can boot up on a PowerPC computer.
What should i do to install 10.5 on an external drive?

Thank You

 

[madog]

FireWire or USB?

The PPC machines can only boot up to external FireWire devices. Even then, I've heard of some FireWire drives can't be booted from. Call it lazy designers or a low-end FW chipset, but that can be the case sometimes.

Also, are you using a a system disk, or a retail disk of Leopard?