Undo using CTRL+Z not working if this is first action in new image

Hi,
using pinta-1.4-preview-20120812 on Windows XP I tested bug https://bugs.launchpad.net/pinta/+bug/983709 which is almost fixed, but now I am opening a new bug, because I can't reproduce the bug in the same way as above bug (I can still reproduce on v1.3), so opening a new one to reduce confusion...

Test 1: Undo works fine with toolbar icon
1. Open Pinta
2. Select Paintbrush and draw something on canvas.
3. Select Text object, click on canvas and type in some text like: test
4. Click Undo button from toolbar. Works fine.

Test 2: Undo works fine with CTRL+Z if some other action was already performed
5. Continue from previous test. Click on canvas (Text object is selected from previous test) and type in some text like: test
6. Press CTRL+Z. Undo works fine.

Test 3: Undo does NOT work fine with CTRL+Z if first action in new image
1. Close image CTRL+W without saving it.
2. Open new image.
3. Select Text object from Tools, click on canvas and type in text like: test
4. Press CTRL+Z and you will notice nothing happens, so undo does not work.
P.S. As I see this time work-around is to press <ESC> key and then repeat CTRL+Z. But <ESC> key was not required in Test 2, and in my humble opinion it should not be required in this test too.