tar on a zip disck

What's the secret to creating a tar archive on a zip disk? I can copy
files and/or directories to and from a zip disk with no problem, but when
I try to create a tar archive, I either lock up or a directory called
lost+found is created on the zip disk that refuses to be deleted (this
as root, mind you!). After the lost+found directory is created, the zip
disk can't be unmounted unless I use shutdown with a reboot.

--

Bob Holtzman
"If you think you're getting free lunch,
...check the price of the beer!"