glGetTexImage unsupported by ATI drivers?

I’m using it to retrieve an imposter texture (atlas) generated at runtime and cache it for subsequent executions.
With nVidia drivers or MESA, I get the correct texture data, but with ATI drivers, only an empty texture (full of zeros) is returned (or sometimes random garbage). The texture seems generated correctly however, it’s just that it can’t be retrieved…

Anyone encountered a similar issue?

Originally posted by EG:Anyone encountered a similar issue?
Yes I’ve had exactly the same problem with a 9800XT. I’ve asked ATI devrel about this issue but got no answer. Fortunately I could use glReadPixels as a workaround.