hey jun_oz -

my best guess is that you need to reboot your ipod into apple's firmware, then connect your ipod to your computer. that's the only way your computer will recognize your ipod as an ipod.

to do so, hold down the menu and play buttons simultaneously for a few seconds. as soon as your ipod reboots, hold the rewind button down. this should launch apple's firmware. then you can connect your ipod to the computer and it should recognize it.