A very recent paper on IIE - and what would it take to make a probe survive to Alpha Centauri?
Includes a diagram of the probe, its main purposes, and issues that need to be worked out.
http://astronauticsnow.com/mg_pubs/2005_Gruntman_et_al_p_29-34_IAA_Aosta.pdf
I also hope they will consider putting a message on it ala Pioneer and Voyager when they reach that stage of the project.
Another thought - what would it take to have such a probe survive to function at Alpha Centauri if it required a century or two to get there, and assuming no one minded the long travel time or that the builders would not live to see the results?