How to use Web Contexts?

HI,

I'm trying to use Web Contexts to solve unresolve refences to files.
I haven't been very successful so far.

A simple example:
I have 2 directory
styles
images
located in a same base directory.

in styles/style.css I want to reference an image with url(../images/pic.gif).
This works in practice but I can't get IDEA to find the pic.gif, no matter what I set as Web Context.
I tried to set the main folder containing styles and images as / but to no avail.

thanks for any help
-nodje