I've been noticing a lot of postings from random obra people where the subject is their name.
Do not open these e-mails, I assume they are infected. And if you do open it, do not go to the link that is in these e-mails. If you have done so, change your e-mail password.
With 5000 of us and a lot of us on obra chat, it is hard to keep it all protected, just keep an eye out for weird postings, and when in doubt, do not open an e-mail.