A while ago, I tried to get JTAG working on my BusPirate with OpenOCD in Windows. I got as far as realizing that I really needed to use Linux for it all to work and put it aside.
Now, after several firmware updates, I can't find JTAG menus at all, unless I'm being really stupid (quite possible).
Is JTAG gone? Is it gone for good, pending the BusBlaster that seems to have JTAG as a primary function???
If you're using open ocd the binary mode JTAG should work even if the terminal mode JTAG is gone. Or you could downgrade the firmware.