Direct Access Broker for Pension Trust Fund

I have a Small Self Administered Pension Scheme (SSAPS). Does anyone know of an online direct access broker that will allow me to open an account for the pension fund (or trust fund) so that I can invest some of the fund directly? I want to be able to buy derivatives as well as stocks.

I have tried Internaxx and TDWaterhouse.co.uk, but both have told me that they will not open a trust account for an Irish based fund.

Thanks all.