How do I erase password protection on an external hard drive?

Dear fellow nerds. I inherited a ½ Gig Lacie external hard drive which I’d like to use as the backup drive for Norton auto backups. Problem is it’s nearly full of my son’s data, and he’s forgotten the password. The Mac Address is printed on a label on the back of it along with a serial number. I see nothing remotely like a model number. It has a USB port and a CAT5 connection for networking it.

I know there is a way to externally wipe out the password and data and reformat the drive from a connected computer. How is it done?