I solved the problem that I posted here on Aug 16, by
replacing the Mitsumi CD-RW with a different model which
knoppix v3.4 is able to mount; the new model registers as an

HL-DT-ST GCE-8525B.

The old, replaced CD-RW Mitsumi CR487-ETE could correctly
mount my knoppix v3.4.0 boot disk as an iso9660 filesystem
when it was driven with Windows2000. Knoppix 3.4.0 .
It could not mount the same boot disk as the same filesystem
when driven by knoppix or Debian(sarge) software
It appears that linux's drivers treat the CR487-ETE differently
than do Microsoft's.