Unfortunately if they were blocked for you they would also be blocked for us Moderators which would make our job rather difficult. If you are being spammed by another member please either reply back with the User Name or send me a private message, OK?
At present at least the PM system is limited to a maximum of 5 messages total in and/or out so a spammer can only send 5 at a time maximum. As Private Messages are indeed private, McAfee can't monitor them. However if someone is abusing the system we need to know about it.
I agree it would be nice if each individual could control that in their own settings but unfortunately Jive SBS which is the host system, doesn't allow that.