HotSpot image controls (web)

MSVC 2005, C# ASP.NET Web page

I need to create a web page to display an image.
I create the image as a Bitmap on the fly (drawn from DB data).
The image may vary in size, as it is a line drawing (image + graph) it has to display in actual size (or detail is lost).
I need the image to respond to mouse clicks (hotspots).

I am currently creating a new page with a hotspot image control. I am passing the bmp to a dummy page (via Session) and streaming the image into the hotspot control page. The hotspots are then set in the hotspot control (via Session).

This results in a few undesirable display issues....

My problem is I can't set the 'image' property of the hotspot image control to a stream from the bitmap or bitmap object. (without saving the bitmap and giving the path, which I am reluctant to do....)

Any suggestions?