RELENG_5: Can't mount NTFS slices

/home/mark{107}# uname -a
FreeBSD redshift 5.3-BETA2 FreeBSD 5.3-BETA2 #0: Fri Aug 27 19:15:05 BST
2004     mark_at_redshift:/usr/obj/usr/src/sys/REDSHIFT  i386

Since building my first RELENG_5 world a week ago (previously running
-current) I cannot mount an NTFS slice:

/home/mark{108}# mount /ntfs
ntfs: /dev/da0s1: Operation not supported by device
/home/mark{109}# grep ntfs /etc/fstab
/dev/da0s1         /ntfs        ntfs    ro,noauto    0    0
/home/mark{110}# ls -l /dev/da*
crw-r-----  1 root  operator    4,  13 27 Aug 19:34 /dev/da0
crw-r-----  1 root  operator    4,  15 27 Aug 19:34 /dev/da0s1
crw-r-----  1 root  operator    4,  14 27 Aug 19:34 /dev/da1
crw-r-----  1 root  operator    4,  16 27 Aug 19:34 /dev/da1s1
crw-r-----  1 root  operator    4,  17 27 Aug 20:34 /dev/da1s1a
crw-r-----  1 root  operator    4,  18 27 Aug 19:34 /dev/da1s1b
crw-r-----  1 root  operator    4,  19 27 Aug 19:34 /dev/da1s1c
crw-r-----  1 root  operator    4,  20 27 Aug 20:34 /dev/da1s1d
crw-r-----  1 root  operator    4,  21 27 Aug 20:34 /dev/da1s1e
crw-r-----  1 root  operator    4,  22 27 Aug 20:34 /dev/da1s1f
crw-r-----  1 root  operator    4,  23 27 Aug 19:34 /dev/da1s1g
/home/mark{111}#

This worked fine in -current. I'm subscribed to this list and haven't
seen anyone else report this and can't find anything in the mail archives.

Can anyone shed any light please?

Thanks.

Regards,

Mark