Time to upgrade. As I recall, Adobe Camera RAW(ACR) was introduced in Photoshop7.0 in quite primitive form. It has come a long way since then. For a digital shooter, this one feature alone warrants not only a software upgrade, but a computer upgrade too if necessary. Of course, Photoshop CS3 has improved to the point that it barely resembles version 6.0.
RAW makes all things possible. I had a difficult shoot a week back, a group met for an outdoor cookout, with rain being likely. The host had spread a translucent blue tarpaulin over the deck, so for much of the day, it was a mix of white ambient light with the intense blue light of the sun hitting the tarp. The dynamic range was also incredible, with those under the tarp in deep shade while the background was in full sun. A processing nightmare.
ACR and layers let me balance for both light-sources, and both light levels, blending everything together so it looked natural with nearly ideal lighting. I was able to do this without having to drop out of 48-bit workspace until I saved the images as JPEGs for the group's web-site. Thus even though the light and blue areas required profound correction to blend, there was no stair stepping or roughness in the gradients. All the blends were perfectly smooth. At twilight, the contrast range increased enormously, so I did a few five-stop auto-brackets with the camera and processed them as HDR (high dynamic range) images holding detail in the sunset and the people who in comparison would otherwise have been in silhouette. Everything in the picture was rich in both shadow and highlight detail with a full range of middle tones. I would not have even dreamed of this with Photoshop6.0.