Since some of the finer details of making this work on the P1620 specifically are strewn about in comments on his blog, etc., I thought I might as well centralize the info and relate my experience with this model.
At first, I tried installing the driver on Ubuntu 10.10 which failed so I reloaded the laptop with 9.04 and loaded the driver which worked nearly out-of-the-box.
I've put a copy of Zmiq2's driver on my Google Sites storage and created a tinyurl for it which is below. This is the fujitsu-usb-touchscreen-0.3.8 version which is the one I had success with:
Steps to install:
OS: Ubuntu 9.04 Jaunty
Chassis: Fujitsu P1620
sudo make install
3. I was not able to get the rotate or right mouse click features to work using the readme or manual installation of fjbtndrv. So on to calibration... :(
4. In my case, running the calibration tool listed in the readme also did not work. However, there is a workaround... I suggest manually editing the conf files as follows.
a. Run the following command from a terminal...
sudo nano /etc/modprobe.d/fujitsu_usb_touchscreen.conf
...and edit the file to look like this:
options fujitsu_usb_touchscreen touch_minx=108 touch_miny=353 touch_maxx=3911 touch_maxy=4000
b. Then run this command...
sudo nano /etc/hal/fdi/policy/fujitsu_usb_touchscreen.fdi
...and make the MinX/MinY section look like this:
<merge key="input.x11_options.MinX" type="string">108</merge>
<merge key="input.x11_options.MinY" type="string">353</merge>
<merge key="input.x11_options.MaxX" type="string">3911</merge>
<merge key="input.x11_options.MaxY" type="string">4000</merge>
Well, that was the fix for me. Hope this makes the world a better place for someone like it did me!