Wrong Interpretation of y-offset in WGL_ARB_buffer_region ?

I have a problem with using save and restore buffer region with depth and color buffer at the same time: It works fine with a y-offset of 0 when restoring the buffers. The offset also works perfect with depth OR color buffer. But when I try to save and restore depth- AND colorbuffer the y-offset is interpreted wrong for the depth-buffer: A positive offset moves the color up and the depth down. (Using only depth, a positive offset moves the depth up…)
My Code:

Maybe …

Post your graphics card or chipset, OS and driver version.

I tried it on TNT, GF1(256 and DDR), GF2 and GF3. I tried it on Win2000 using Detonator 21.81 and on Win98 using Detonator 12.90