I have succeeded in my project to use the above hardware from the shell.
The hard part is installing SMS on the Arduino. You'll need a system with
Java5 or the GUI will be a mess. You'll also need to 'sudo apt-get install
gcc-avr avrdude'. These are the cross-compiler and the loader. The GUI for
linux is Arduino-0010, recently released for linux. Or maybe you can get
someone to load the hardware for you. Google will find SMS &etc.

About my shell scripts: Run this now: 'wget http://207.14.167.161/SMS1.tgz'
It only works when my system is booted, so keep trying.

rolandl@desktop1:~/bin$ ls;echo;cat readme.txt
convert ledOff-1 readAD-1 readme.txt wait4pin-1
gpl.txt ledOn-1 readIO-1 setup-Arduino writePin-1

# by Roland Latour, Feb.2008, GPLv3, see gpl.txt, included
# email: rolandl@cavenet.com
For Arduino Diecimila with USB, loaded with Simple Message System
Don't forget to change the baud rate from 9600 to 115200 before
you click on compile-and-load.

Many of these files may look strange, because they contain embedded ^M
characters. I used vi to create them. I suggest you put them in $HOME/bin
and make sure that's in your $PATH.

First, 'source setup-Arduino'. This sets port parameters then starts a
helper process to catch output from the Unit (from read commands)
and stuff it into logfile1.raw. Run 'jobs' to see it.

Write commands are easy, they shouldn't need a helper process. But it seems
they only get reliable when the helper is running. I don't know why.

Read commands are very similar to write commands, but they use the command
'tail -1 logfile1.raw'
to get their data. The 'sleep 1' is necessary because the helper is slow.
I found it useful to run 'tail -f logfile1.raw' in another window
during read commands, especially for timing purposes.

When you unplug the unit, its device node goes away, which kills the
helper process.

Finally got the right data format from readAD-1: Comma-separated values
with timestamp, in logfile.csv: 13:38:56,1016,3279,3191,4999,3895,0
It shows values scaled to MilliVolts: ch1=3.3v, ch3=5v, ch5=gnd, others float.
This imports to OpenOffice calc easily, for further analysis or graphing.

Commands ending with -1 are to operate/test UNIT1. Setup-Arduino can be
fixed up for expansion. Need more pins? Plug in another SMS-loaded unit!

To Do:
1)finish the wait4pin command
2)I think linux needs a repeat command
3)create PWM program: syntax: 'writePWM-1 pin# 0-255'
where pin#=3,5,6,9,10,11 and 0-255 gives 0-100% duty cycle
The official website http://www.arduino.cc/en/Reference/AnalogWrite says:
The frequency of the PWM signal is approximately 490 Hz.