Lost Time Machine Password - Unable to Format Disk I lost my password to my Time Machine backup. It's on a Seagate FreeAgent USB drive. I don't mind losing the data, I just can't figure out how to format the drive. I found this thread, however, the "Erase" tab that's mentioned doesn't appear when I select the drive. It's also grayed out for the partition.

I've tried running VirtualBox and accessing the drive in Windows, but the FreeAgent drive is grayed out as one of the available devices.

I've also tried hooking up the disc to a Windows XP machine and running the EaseUS partition tool, but that tool doesn't give me the option to format (as if it was grayed out).

Any thoughts or ideas?
you've probably answered this already, but you need to use the terminal. 

diskutil list

and then

diskutil eraseDisk nameofnewdisk /dev/diskX

replace diskX with disk0 or disk1 or whatever from diskutil list