How to tell Knoppix hw clock is local time, *not* utc?

["Andrew" <knoppix@rngresearch.com>]

Dear Klaus et al,

Some of the machines on which I run Knoppix must keep their hardware
clocks set to the local time (because they primarily run ms windows).  The
problem is that Knoppix incorrectly interprets and records incorrect file
timestamps.

Using
    boot: ...tz=locatime...
dones't work.  Knoppix still sets the system clock incorrectly; it just
reports the wrong time in UTC.

    boot: ...tz=<something else>...
doesn't work.  Knoppix sets the system clock to the same wrong time; it
just reports the wrong time in <something else>.

How can I get Knoppix to set the system clock to the correct time?

Warm regards,
Andrew