Advanced buffers

I love the memory mamagement of the OpenGL 2.0
proposal, but i have and idea of something that could be added:
A buffer should be able to be used to do a lot of
things (for instance render to texure, shadow casting,…).
Couldn’t i try to create custom buffers like this:

buf = CreateBuffer(Z_BUFFER|TEXTURE);
UseBufferAs(buf,Z_BUFFER);

draw_something();

UseBufferAs(buf,TEXTURE);

draw_something_else();

Using the content of the buffer (zbuffer, stencil or color) as texture, or to render shadows…

This was just suggestion…

You can detach any buffer from the render target and attach it to texture.

So OpenGL 2.0 supports render-to-texture.