I do not have the latest knoppix cd, however on my customized knoppix (w/ the orinoco patch), i was able to put it into monitor mode using this:
Code:
iwpriv eth0 monitor <m> <c>
   m - one of the following
      0 - disable monitor mode
      1 - enable monitor mode with Prism2 header info prepended
          to packet (ARPHRD_IEEE80211_PRISM)
      2 - enable monitor mode with no Prism2 info (ARPHRD_IEEE80211)
   c - channel to monitor


Change your MAC address via ifconfig:

ifconfig eth0 hw ether 01:02:03:04:05:06