Throws null ref exception

MyCustomControl.as

package
{
	public class MyCustomControl
	{
		protected var someDependency:Object;
		
		[Bindable]
		public function get someProperty():Object { return null; }
		public function set someProperty(value:Object):void
		{
			someDependency.someMethod(); // throws a null ref exception that gets swallowed
		}
	}
}

View.mxml

<?xml version="1.0" encoding="utf-8"?>
<mx:Box xmlns:mx="http://www.adobe.com/2006/mxml">
	<MyCustomControl someProperty="{this}"/>
</mx:Box>