Change color of a line separator in Cocoa

Is there is any way to change the color of a line ("vertical line" and "horizontal line" of Interface Builder). A line separator in IB开发者_运维问答 is a NSBox and I didn't find any method to change color when is used as NSBoxSeparator.

It doesn't look like the line color is exposed for the "line" convenience object, but it is for the regular NSBox.

You can use a regular NSBox with its Box Type set to Custom and its border color set to whatever you desire. Then just size it down to a single pixel width or height.