Python windows kit tcl version conflict

[HardYards]

I have just installed tcl 8.4 from scratch - have never used it before
and also installed python (I am trying  to use VTK and Mayavi) and
have found that IDLE won't run.

It is coming up with the - apparently common - tcl error 

TclError: Can't find a usable init.tcl in the following directories:
    D:/Tcl/lib/tcl8.4 {} D:/Tcl/lib/tcl8.4 D:/Tcl/lib/tcl8.3
D:/Python22/lib
8.3 D:/lib/tcl8.3 lib/tcl8.3 lib/tcl8.3/library library
../tcl8.3/library.

The trouble is I have never had tcl 8.3....

Anyway after searching the system for anything with an 8.3 in it's
name and I have found that python installs some tcl 8.3 libs (In the
windows installer release).

I have tried renaming these so they can't be found. adjusting
TCL_LIBRARY etc etc. But I am getting  the same error.

Where is it picking up the 8.3 bit from and how do I get python to use
the installed tcl libraries.

Totally stumped....