Please describe the problem:
When creating grayscale animated brushes that you want to colour using the colour picker, the resulting brush turns into a filled black square. This only happens if you pick grayscale mode before saving the brush. Full colour brushes work fine (Image>Mode>RGB).

Steps to reproduce:
1. Create a new image.
2. Create multiple layers and doodle on each one for your animated brush.
3. Select Image>Mode>Grayscale
4. Save the brush as .gih
5. Put the brush in your brush path.
6. Reload the brush pallette to load the brush.


Actual results:
I get a brush that is just a black block, rather than the one I created.

Expected results:
I expected to get an animated brush that I could pick the colour of when painting. (Note. That the existing animated brushes, like Pencil Sketch#1, work just fine).

Does this happen every time?
Yes.

Other information:
This is tested on Ubuntu 8.10, using GIMP 2.6.1 found in the default Ubuntu repository. Animated brushes add a lot of power to GIMP when painting with it and are kind of important. This used to work in previous versions. Couldn't find a previous report on this or any note on it being fixed in more recent versions, so I'm assuming it's still a bug in 2.6.3.