A Thunderbird plugin can prevent these Email Leaks (Score 1)

Researchers in Carnegie Mellon University developed a Mozilla Thunderbird plug-in that can prevent these email gaffes, or email information leaks. Pretty neat idea.

http://wcohen.blogspot.com/2008/01/measure-twice-cut-once.html

The original idea: http://www.cs.cmu.edu/~wcohen/#sw and http://www.cs.cmu.edu/~wcohen/postscript/sdm-2007-leak.pdf

I've just installed it. Seems to works for me.