Disappearing background images?

I haven’t had any problem using background images until now. I Load and Pack the image into the UV/Image Editor then Save the .blend file. The images have always been there after reopening the file in 2.49x, Alpha0, 1 and 2. Now some images aren’t there after reopening with 2.49b and Alpha2’s most recent GraphicAll builds. I must be doing something different, but don’t know what. Any ideas?

d2

fake user them, or make sure they are being used for something, like a texture, or, in order to keep file size down, they are not loaded if they are not used.