Double buffering Form.Canvas Keep AlphaBlend?


I am currently drawing directly onto the Form.Canvas use the DrawText API
call.  The form is AlphaBlended using Form.AlphaBlend etc properties.

Every so often the form flickers on and off.  Is it possible to stop this -
I think I need Double Buffer but as I want to keep the "transparency" I do
not think a simple intermediary bitmap will suffice as transparency will be

Does anyone have any ideas on the best method to solve this problem -
example / pseudo code?