iPhone is it possible?

I have setup a normal iPhone UIView suface that is behind the main Edgelib opengl surface.
I need the Edgelib opengl surface to be transparent so that I can render in 3D, but still see the normal iPhone surface behind.
I am going down the route of seting up edgelib to be 32bit RGBA and use the alpha to create the see through transparent, but no sucess yet.
All I get is black not transparent
In (OnDisplayConfig)
config->videotype = EDSP_TRUE32_INV;
Which tells edgelib to set the back buffer to 32bit RGBA
does this work on the iphone?
Then when loading in a 3D model
EST_READONLYPATH|EST_DSPTRUE32_INV
Which tells edgelib to create a 32bit RGBA model
What am I missing or is there another way?
I need the Edgelib opengl surface to be transparent so that I can render in 3D, but still see the normal iPhone surface behind.
I am going down the route of seting up edgelib to be 32bit RGBA and use the alpha to create the see through transparent, but no sucess yet.
All I get is black not transparent
In (OnDisplayConfig)
config->videotype = EDSP_TRUE32_INV;
Which tells edgelib to set the back buffer to 32bit RGBA
does this work on the iphone?
Then when loading in a 3D model
EST_READONLYPATH|EST_DSPTRUE32_INV
Which tells edgelib to create a 32bit RGBA model
What am I missing or is there another way?