I think Hushmail made the same claims, until compelled by law enforcement to send altered client software to the machines of suspects. Not sure how these other

I think Hushmail made the same claims, until compelled by law enforcement to send altered client software to the machines of suspects. Not sure how these other companies operate, but unless the user hand-encrypts files with openssl, gpg, pgp, etc., then the trusted client software has the potential to be a vector for compromise.