I think, I got the problem...
First: I'm creating the directory /mnt/usb with mkdir as root. Then I edit the /etc/fstab with vi (also as root) and add the following entry:
/dev/sda1 /mnt/usb auto noauto,owner,kudzu 0 0
I simply copied the entry from the floppy, but now I will try to leave the "kudzu" entry. I can tell you tomorrow, if this solves the problem...
But there remains one question: Why does the floppy-entry stay
Thanks for your help,