I tried not to come with too newbies question, but was not able to find a proper answer to this:

I'm trying to modify an NTFS harddrive mounted with Knoppix. I'm quiet well aware that this is very risky and not supported, at least by linux (reading FAQs and all) .

The modification I'd like to do are very simple (rename file like foo.dlx to foo.dlx.tej or whatever).

But even this is not permitted. It looks like I'm definately not able to mount any NTFS drive in RW mode.
Even if I'm using the "mount -o remount,rw /mnt/<whatever>" or unchecking the read only attribute on the icon proprety, or event mount manually the file system with a command like : "mount -o rw -t ntfs /dev/hda1 /mnt/hda1". In the latest, a "mount" command show me that the partition is mounted as "rw", but if I just try to "touch" a file, the system tells me it's still a read only filesystem.

Is this a new feature of the new version ? Is there a way to workaround this behavior?

Again, I don't really want to do very destructive modifications, and if they happen, I can assume I'm the only responsible of it, but at least, I'd like to be able to try them...