Steps to reproduce:
1. Install hamster-applet svn
2. Add it to a panel but nothing appears
3. run in it in window mode ( -w ) and get a python traceback due to to a crash


Stack trace:
/usr/lib/hamster-applet/hamster-applet -w
Running installed hamster, using [/usr/lib/python2.5/site-packages/hamster:$PYTHONPATH]
Data Dir: /usr/share/hamster-applet
SELECT version FROM version None
UPDATE version SET version = 4 ()
select count(*) from categories None
Binding shortcut <Super>S to popup hamster

** (hamster-applet:3020): WARNING **: Binding '<Super>S' failed!

Running with options: {'do_trace': False, 'standalone': True}
/usr/lib/python2.5/site-packages/hamster/applet.py:284: GtkWarning: gtk_cell_layout_set_attributes: assertion `GTK_IS_CELL_RENDERER (cell)' failed
  self.activity_list.set_property("text-column", 2)

                   SELECT a.id AS id,
                          a.start_time AS start_time,
                          a.end_time AS end_time,
                          b.name AS name, b.id as activity_id,
                          coalesce(c.name, ?) as category, c.id as category_id
                     FROM facts a
                LEFT JOIN activities b ON a.activity_id = b.id
                LEFT JOIN categories c on b.category_id = c.id
                    WHERE date(a.start_time) >= ? and date(a.start_time) <= ?
                 ORDER BY a.start_time
         ('Unsorted', datetime.date(2008, 11, 2), datetime.date(2008, 11, 2))

                   SELECT lower(a.name) as name, b.name as category
                     FROM activities a
                LEFT JOIN categories b on coalesce(b.id, -1) = a.category_id
                    WHERE deleted is null
                 ORDER BY lower(a.name)
         None

                   SELECT a.*, b.name as category, b.category_order
                     FROM activities a
                LEFT JOIN categories b on coalesce(b.id, -1) = a.category_id
                    WHERE a.category_id > -1
                      AND a.deleted is null
                 ORDER BY category_order, activity_order
         None
** (hamster-applet:3020): DEBUG: Opening calendar source uri: file:///home/iamer/.evolution/tasks/local/system

** (hamster-applet:3020): DEBUG: Opening calendar source uri: file:///home/iamer/.evolution/tasks/local/1223484641.7362.0@phoenix

** (hamster-applet:3020): DEBUG: Opening calendar source uri: file:///home/iamer/.evolution/tasks/local/1225186443.5668.0@phoenix

Traceback (most recent call last):

+ Trace 209090

Other information:
I debugged the problem and it seems to happen because the view and model for storing tasks and categories changed, but tasks gotten from evolution were not updated to be stored in the same way.

I will include a patch that fixes this for me by setting the category to the task list's name.