Sorry for the newb question, but I believe my address on bitfunder was one I created on my bitcoinqt wallet, does that mean it's one I can sign messages with?
It would be really great if someone could post a quick how-to so that everyone can check that they can do this before the shut-down, otherwise there will likely be many tears.
I am sadly too busy to do this, but am just throwing this out there as an invaluable suggestion...