Definitely. Also, I don't know anything about their relations, but if this is a client machine, first thing to do would be to contact the client telling him tha

Definitely. Also, I don't know anything about their relations, but if this is a client machine, first thing to do would be to contact the client telling him that his box is compromised and if he wants me to investigate. Otherwise, from a non-technical person view, the whole (awesome) story looks like somebody attempted to do something with e-mails and he failed.