Eventually I solved it with some help from BR0KK.

Here is how I did it...
1. Click on the start menu and type RUN and hit enter. You will see the RUN window, type hdwwiz in the Open field and click OK button.
https://dl.dropbox.com/u/704649/ztex%20driver6.png

2. It will open "Add Hardware Wizard" as shown in the screenshot below. Click "Next" button to proceed to next step.

3. Choose "Install the hardware that I manually select form a list (Advanced)" and click "Next" button.

4. Choose "Show All Devices" and hit the "Next" button.

5. Click "Have Disk" button and browse to ztex-120412\ztex\libusb-win32\ztex.inf at the downloaded SDK folder.

https://dl.dropbox.com/u/704649/ztex%20driver4.png

6. Select the "Ztex module" and click "Next" button.

https://dl.dropbox.com/u/704649/ztex%20driver5.png

7. Click "Next" to skip final window before the installation will begin.

8. Click on the "Finish" button to close the wizard.

9. I then had to power off the Ztex module.

10. When it come up again it was recogniced as a Zetex module and it was possible to run the "java -cp ZtexBTCMiner-120703.jar BTCMiner..." at the CMD promt to start mining.