Unable to unmount with nautilus script

[ucal]

I downloaded and used this script:

http://mundogeek.net/nautilus-scripts/#nautilus-mount-image

However, I am unable to unmount anything mounted with it. I get this error:

umount: /media/example.iso is not in the fstab (and you are not root)

Is there a way to use SUDO to do this? Or a way to fix the script so I can enable administrative privileges upon unmounting an iso?

[youthforlinux]

You could use the terminal and run the script as root or use gksudo.

[ucal]

The odd thing is that the script asked for the password to perform administrative tasks when I was mounting the volume, but it didn't when unmounting. So I'll figure out what the script is called and use sudo with it for now, but I'd really like a fix that means I don't have to use the terminal.