ActionScript 3.0 :: Protected Set Functions - Cannot Access From Child Classes

I have this function in the parent class:
ActionScript Code:
private m_colors:Array;
protected function set colors(clrs:Array):void {
m_colors = clrs;
}

Then, in my child class I want to call this as:
super.colors = [15, 255];
But it throws an error, it says:
Ambiguous reference to colors. If I do the same with a common function, not a setter one, then just calling it with its name in my child class works fine.