IE 8 Slipstreaming...

Recently I have tried to slipstream IE 8 into Vista SP2 image. When I try to
use the image it runs through the setup. It then tells before 1st login that
it is reverting back updates were not successful, and when I login, I have
IE7 not IE8 installed. I have done this with a Vista SP1 image and it works
fine when integrating IE8. Has anyone else had this problem or know of a
solution?

Thanks,
Ross