Again problems with mounting a dvd

Dear All

I am again having problems with mounting a data dvd. In /etc/fstab, I
have the line

/dev/hdf /mnt/dvd udf,iso9660 defaults,noauto,user,exec,ro 0 0

But,

$ mount /dev/dvd
mount: wrong fs type, bad option, bad superblock on /dev/hdf,
      missing codepage or other error
      In some cases useful info is found in syslog - try
      dmesg | tail  or so

$

and

$ dmesg | tail
attempt to access beyond end of device
hdf: rw=0, want=68, limit=4
attempt to access beyond end of device
hdf: rw=0, want=1252, limit=4
attempt to access beyond end of device
hdf: rw=0, want=1028, limit=4
UDF-fs: No partition found (1)
attempt to access beyond end of device
hdf: rw=0, want=68, limit=4
isofs_fill_super: bread failed, dev=hdf, iso_blknum=16, block=16
$

Any ideas?

Thanks in advance,

Paul