Connecting a Lacie external HD through USB to My Book World Edition HD

I have connected my 2-3 years old Lacie external HD (Ethernet Disk Mini, 500 Mb) to the USB port of My Book World Edition HD, but it doesn’t detect it. They said it should appear as a shared folder.

Is there any driver I could use ? I couldn’t find it on the drivers list on the WS web.

Thanks. 

When you connect a external usb to a my book world it will be used for extra storage not its own drive.