I would be nice, if /usr/sbin/rebuildfstab could detect if ntfs-3g is installed an replace the "ntfs"-type with an "ntfs-3g" one.
Digging deeper into that problem, I noticed that the easiest way to fix that should be to modify /usr/sbin/fstype by adding [ "$FSTYPE" = "ntfs" -a -x /usr/local/bin/mount.ntfs-3g ] && FSTYPE="ntfs-3g"
just before the finalecho "$FSTYPE