Have you contacted this list?
"Several of these IRAs PENSCO, EnTrust, Equity Institutional, and Millennium Trust, are now listing the BIT as an investment option. " (It's linking back to the SecondMarket BIT fund)
From what I read, to be able to purchase you have to make over 200,000/year and make a minimum investment of 25,000. I could almost make the 25,000 investment, but they would laugh at me when they find out how much a year I make

I'm a Pastor