I am wondering how it is possible to get rid of (or change color) titleDivider in Dialog. It is a blue line below dialog title shown on honeycomb+ devices.
Your idea was correct. However, dialogTitleDecorLayout you were looking for is a private resource, so you can't access it in a normal way. But you still can access it using * syntax:
- @layout/dialog_title
Adding this to my own style and simply copying dialog_title.xml to my app and changing it slightly solved the problem in my case.