Unable to delete notes for a completed number

When using the option "Disable completed numbers", it's not possible to 
delete notes for a number which has already been completed.

- What steps will reproduce the problem?
1. Enable the "Disable completed numbers" option
2. Create notes for a number, say, number 4.
3. Complete all the 4s in the puzzle (button for number 4 becomes disabled)
4. Try to delete the notes for number 4 in the other squares -- it's not 
possible because the button for number 4 is disabled.

- What is the expected output? What do you see instead?
Expected being able to delete the notes after completing the number.
The buttons should always be enabled in notes mode.

- What version of the product are you using? On what operating system?
OpenSudoku 0.7.0, on Android 1.5

Original issue reported on code.google.com by cach...@gmail.com on 10 Nov 2009 at 7:18

Merged into: #42

gcm2406 / opensudoku-android

Unable to delete notes for a completed number #50