I think once I get this mess sorted out, I'm going to upgrade permanently to MT4.1 and clear out some of the old cruft - the version I've been using is 3.34, as I've been too lazy to upgrade so far.

As far as I know, none of the standalone blog software has privacy filters, probably because it really requires registration of some sort to be secure, and that only really works well with some sort of central server system where everyone uses the exact same codebase, like LJ. I don't flock much, so it's not really a big deal for me, but I get where you're coming from.