workflow_access permissions not aligned with roles

Hello, I found something extremely fishy while testing workflow_access. Here is the recipe to show the issue:

- Install a stock Drupal 6.4. Add workflow-6.x-1.0-rc1, enable workflow_access, rebuild permissions.
- Add a role called 'contributor'
- Add a user called 'user', add role 'contributor'
- In Permissions, add 'create page content' to 'contributor'
- Add a new workflow 'Work'.
- Assign 'Work' to Page (Post), save.
- Add one state called 'Editing'.
- Edit workflow. Enable transition from '(creation)' to 'Editing' for author.
- Workflow tab permission: author
- Roles who can view posts in the state 'Editing': author. Uncheck the rest. Save
- Now, log in as 'user'
- Create a new page. Save.
- The page is shown to user 'user'.

So far so good, 'user' is the author and so has permission to view the page according to the permissions set in the 'Editing' state.

Now:

- Create a new role 'strange'
- Have a look at the permissions in the 'Editing' state

'author' no longer has permission to view, which mysteriously moved to the 'strange' role. Let's make things worse.

- Delete the 'contributor' role.
- Delete 'strange'.
- Add a new role 'xx'.
- Go back to the workflow, and look at access control for 'Editing': 'author' regained by itself its 'view' permission.
- In Permissions, add 'create page content' to role 'xx'.
- Give the 'xx' role to 'user'.
- Log in as 'user' again and try to create a new page. When you save the page, despite the author having 'view' permissions, you get:

Access denied
Article uuuu has been created.
You are not authorized to access this page.

-- Table contents

What is going on? An inspection of the tables reveals the following:

- When creating the first page, this is the content of the tables:

mysql> select * from node_access;
+-----+-----+-----------------+------------+--------------+--------------+
| nid | gid | realm           | grant_view | grant_update | grant_delete |
+-----+-----+-----------------+------------+--------------+--------------+
|   1 |   3 | workflow_access |          1 |            0 |            0 | 
+-----+-----+-----------------+------------+--------------+--------------+
1 row in set (0.00 sec)

mysql> select * from workflow_access;
+-----+-----+------------+--------------+--------------+
| sid | rid | grant_view | grant_update | grant_delete |
+-----+-----+------------+--------------+--------------+
|   2 |   3 |          1 |            0 |            0 | 
|   2 |   0 |          0 |            0 |            0 | 
|   2 |   1 |          0 |            0 |            0 | 
|   2 |   2 |          0 |            0 |            0 | 
+-----+-----+------------+--------------+--------------+
4 rows in set (0.00 sec)

mysql> select * from role;
+-----+--------------------+
| rid | name               |
+-----+--------------------+
|   1 | anonymous user     | 
|   2 | authenticated user | 
|   3 | contributor        | 
+-----+--------------------+
3 rows in set (0.00 sec)

I don't know much about the inner workings of workflow_access, but the grant_view for rid '3' seems wrong to me. After creating the 'strange' role, the table becomes:

+-----+--------------------+
| rid | name               |
+-----+--------------------+
|   1 | anonymous user     | 
|   2 | authenticated user | 
|   3 | contributor        | 
|   4 | strange            | 
+-----+--------------------+

and the workflow_access table is unchanged, which explains why the privilege shifts unexpectedly. After the further changes, the tables become:

mysql> select * from role;
+-----+--------------------+
| rid | name               |
+-----+--------------------+
|   1 | anonymous user     | 
|   2 | authenticated user | 
|   5 | xx                 | 
+-----+--------------------+
3 rows in set (0.00 sec)

mysql> select * from workflow_access;
+-----+-----+------------+--------------+--------------+
| sid | rid | grant_view | grant_update | grant_delete |
+-----+-----+------------+--------------+--------------+
|   2 |   2 |          0 |            0 |            0 | 
|   2 |   1 |          0 |            0 |            0 | 
|   2 |   0 |          0 |            0 |            0 | 
|   2 |   3 |          1 |            0 |            0 | 
+-----+-----+------------+--------------+--------------+
4 rows in set (0.00 sec)

The situation becomes even more messy as more roles are added and removed; no amount of 'rebuild node permissions' will fix the situation.
It would be quite helpful if any of the people who know about workflow_access could give their opinion (and suggest a way for me to make the whole thing work as expected).
Thanks!