Windows Driver for USB to RS232?

Here's the more latest:

1. prolific has a new version of their driver as of April 2009.  It fixed
my bug this week.
See http://prolific.com.tw/ and follow the usual product/support/download
links until you get somewhere like this: 
http://www.prolific.com.tw/eng/downloads.asp?ID=31

2. ftdichip.com does seem to be the best stuff out there.

3. I'm using the Windows Java Serial Com Port Driver
from http://www.engidea.com/blog/informatica/winjcom/winjcom.html
It is much, much better than RXTX and very appropriate for removable
serial ports (USB serial ports).

-Stosh