In the meantime I work with Ubuntu 10.4. Today I could see and reproduce this steps:
1. Boot the system.
2. I don't make a graphical login, only a console login.
3. sudo mount /dev/fd0 /mnt # I can work on disk
4. Graphical login (gnome)
5. After step 4, the fd0 is not mounted any more! Remount is impossible.
In the meantime I work with Ubuntu 10.4. Today I could see and reproduce this steps:
1. Boot the system.
2. I don't make a graphical login, only a console login.
3. sudo mount /dev/fd0 /mnt # I can work on disk
4. Graphical login (gnome)
5. After step 4, the fd0 is not mounted any more! Remount is impossible.