[FWTools] How can I use my own python instead of the default python in fwtools windows bundle?

[Litao Wei]

I want to test fwtools and PCL on my windows. The PCL documents say for 
install FWTools, just need simply add its Python
module path ('FWToolsx.x.x\pymod') to your PYTHONPATH environment 
variable. But I don't know where to add, for I use Zope bundled python, 
there is no register entry for PYTHONPATH.