Other articles go into details about Ivins use of an anonymous PO box in which he received bondage porn (I won't even bother linking to those). Why this is important, I don't know. Did the sorority get Anthrax letters? No. Did any former or current members get anthrax letters? No. And could officials place Ivins at the scene of the mailings? No. But for some reason this is what the Feds are leaking to the press. You have to wonder why that is.
Remember back in the JFK assassination, there was a claim that Lee Oswald ordered the rifle by mail and had it delivered to a PO box in the name of his supposed alias A. Hidell. Given that Oswald could have bought a gun without any ID at any Texas gun store, the creation and use of the mailbox appears to be part of the frame-up. Given how easily porn is obtained over the internet for free, one has to wonder why anyone would set up a PO box and pay for porn to be sent there ... unless it is a part of the frame job to help destroy Ivins' public image.