HD 4870 and OpenGl seems to work (cat 12.1)

Hello!

I've read in the Known Issues section that newer Catalyst drivers wouldn't support normal maps. Since I always like to get the most out of my games I tried the suggestion to install older catalyst drivers although everything appeared to look fine with my currently installed catalyst 12.1 version (I have no idea what normal maps should look like, by the way). So I installed version 10.4 to see if it's any different but I couldn't make out anything for the better or worse. I even made some before/after Screenshots but I still fail to see the difference let alone any kind of graphical glitch. By the way, the solution to put the old 10.4 atioglxx.dll into the WC Saga directory doesn't work - the game just crashes on startup with a generic windows error (don't know how it translates into english, since I have a german windows XP).
Anyway, I'm curious about this and would like to know if I'm just blind or if this bug has already been fixed in the 12.1 version or if it doesn't concern my graphics card although it's a 4xxx. Here are the screenshots I made:

Catalyst 10.4

and with Catalyst 12.1

I failed to get the angle to the sun right in the second but both still look right to me. On a side note - Anti Aliasing also works fine (didn't activate it for the screenshots, though).

Specs:
WinXP Pro 32Bit
Sapphire ATI Radeon HD4870 1GB

One screenshot uses shaders, the other the fallback graphics. So the shaders don't compile with one of the drivers used.