EditorUtility.CopySerialized crashed Unity

Simply code:

GameObject so, de;
...
if (GUILayout.Button("CopySerial"))
{
    if (so.GetComponent<BoxCollider>() != null  de.GetComponent<BoxCollider>() != null)
        EditorUtility.CopySerialized(so.GetComponent<BoxCollider>(), de.GetComponent<BoxCollider>());
}
...

leads to crash.
GameObjects so de is simple Default Cube’s

in EditorLog:
"
o == NULL
UnityEditor.EditorUtility:CopySerialized(Object, Object)
"

Who met this?

http://answers.unity3d.com/questions/8622/what-is-editorutilitycopyserialized-supposed-to-do.html

Seems like an old bug “Dec 03, 2009”