I came across this when I was trying to figure out a command line method of starting PPP. I checked the process list, and was surprised to find that the password for my internet account was listed there. You can test this yourself by typing (in the terminal):
ps auxww | grep "pppd"This will list the full command that starts PPP. It includes your username and password as well as the telephone number used and any other configuration information. Basically everything needed to use YOUR internet accout.
Mac OS X Hints
http://hints.macworld.com/article.php?story=20020510091201613