obviously it’s not possible to eject a disk in a standard user account in Panther
You will be asked for admin username and password.
So I tried a script with
do shell script "sudo /usr/sbin/diskutil unmount /Volumes/xxxx" password "¢¢¢¢" with administrator privileges
(in Panther there is no user name parameter) and got an error “wrong password attempt”
thanks for the response. I forgot to mention, that I tried everything with/without sudo,
with/without password, with/without full path, user password/admin password.
I think, Panther behaves quite different in this case as Tiger does.