I noticed that after changing the status field, the screen is updated, according to the workflow configuration. However, I noticed that sometimes the screen is not updated as expected. I found out that this behaviour occurs when I am a user that has a role without permission to add new issues.

Example:
1-Consider an issue in "New" status.
2-Log on with a user "John" that has a role unable to create new issues (only update).
3-John changes the issue status to "Analysis".
4-Screen refreshes the group of fields presented to him.
5-Consider that there is a mandatory field to be filled in when the issue status is "Analysis" (not showed in "New" status).
6-However, the screen does not show that mandatory field.

But, if we go to workflow configuration admin page and enable John to add new issues and repeat the previous steps, the mandatory field is there as expected! However, we would not like to enable John to add issues...

Environment:
Redmine version 2.1.2.stable
Ruby version 1.8.7 (x86_64-linux)
Rails version 3.2.8
Environment production
Database adapter MySQL