Textfield background color and SDK

I found some very annoying and weird thing. When I compile my app using =
the 10.5 SDK (on Xcode 3) the textfields in web pages from WebKit =
(without style) have a black background color. When compiled using the =
10.6 SDK, they're properly white. This seems absolutely wrong. But I =
don't have an idea why this is happening. Does anyone have an idea? I am =
very sure that this was not happening a while ago with the 10.5 SDK. I =
do need it though, as I want to 10.5. I figured out that the text fields =
have a clearColor set for their backgroundColor by WebKit. Anyone have =
an idea why this is happening, and whether there's a workaround?

thanks,
Christiaan