While this does not answer your question Irongeek, I found just one other site, besides your tuts that have some helpful information on ettercap:

http://securitypronews.com/securityp...andBeyond.html

While not an expert on this, what you have in your code should work. I will see if I can find something else and also bounce this it off a few peoples.

Just to ask the stupid question:

1. Do you need to "touch" the logfile.log before running Ettercap?