Making a bootable USB Drive from an .iso I have a copy of the Windows XP install disk on my computer in the form of an .iso. I'm trying to install it to a partition using a bootable USB. I need to be able to make a bootable USB under Lion. How would I do this?

The USB is 4GB

EDIT: Got my VM working and I'm using a windows utility to make my USB drive bootable. I'll see how it works and post here when I'm done.

Also forgot to mention, according to Apple's Website my mac can handle XP. They just don't provide the software with lion to do so.

EDIT 2: Managed to get started, but not enough. Using my Windows XP VM and a program called "rufus" I made a bootable USB. Then using rEFIt I booted it up. But I got the following screen:
The simple process is to use Apple's Bootcanp to handle three problems you face in booting from windows:


Partitioning your internal drive (you can skip this - it's what Bootcanp wants, but purely optional)
Supply drivers - XP almost certainly won't have correct drivers for new Macs. Since you didn't mention your hardware, it might be old enough to not matter. 
Ensure the Mac EFI sees and initiates boot - this is where making a bootable USB trips up most users. 


You'll want to look at a tool like rEFIt, rEFInd or bootrunner since just burning the image onto USB is not enough to boot foreign OS like an XP live CD image. 

If that image doesn't include an EFI aware boot loader, you'll need to modify that ISO and wrap it in a boot loader such as GRUB.