"I wonder if this is coming from some other poor bugger who's infected ?"

Yes, I think this is the case. I thought I remembered getting a legitimate explicit request for the ATS5xISP program (which I have since put up on my 8052.com user page) from a cordial fellow with a .yu domain. I looked back and there he is in my saved e-mails! I'll send a kind note back to him in case he isn't aware of his "infection".