How to adjust color for highlighting items (e. g. files in Transfers tab) (Linux)

Although the latest Linux builds do provide an amazingly large list of color settings (Window bg, Input fg etc.), it seems that the color of the "beam" which selects files, users etc. is always unaffected of these settings.

Surprisingly enough, this color CAN get modified in a very limited way: by setting the Qt Look & Feel (Cleanlooks, Plastique etc.)

However, I have no idea where it actually takes these colors from.

Another interesting read about this subject is this:
http://stackoverflow.com/questions/6740333/can-i-run-a-qt-application-wi...