How to change the color of markers on the scroll bar?

In Zend Studio (or Eclipse PDT) when you select a property/method the scroll bar shows markers of where else in the source file it's referenced.

I have a problem seeing the those markers. They are to close to the same color as the scroll bar and when my eyes are tired it's really hard to see.

Is there a way to change the colors of these markers to something different (like bright green).

Even in the attached sample image they are hard to see. So I circled them in red.

enter image description here

Solution

Go to Window > Preferences, and at the top, search for: Annotations.

I believe, the ones you're looking for will be under General > Editors > Text Editors > Annotations.