Please describe the problem:
When I try to save a change to a recurring appointment on the evolution
calender, I receive an error message saying "Object ID already exists,"
and am forced to discard the change in order to close the edit window and return to the calendar.


Steps to reproduce:
1. Open an existing recurring appointment on the calendar
2. Make a change to any item
3. Click the save button -- Option window opens asking whether to change only this occurrence to change all. 
4. Select either option (The problem occurs regardless of which choice
is made.)  - Error window opens stating "Object ID already exists"
5. click OK or close window -- this will return you to the modified appointment
6. attempt to close the window using any method -- window opens telling you changes have been made and asking if you wish to save them
7. only option that gets you out of the edit mode is "Discard Changes"

Actual results:
it depends on which choice you select in the save choices window.
If you select save changes it takes you back to "Object ID already exists"
If you select cancel it takes you back to the edit window
If you select discard changes it takes you back to the calendar without saving changes

Expected results:
when I click on save changes, the edit window should close and I should be returned to calendar which should show the changed information

Does this happen every time?
Yes

Other information:
Distribution: Ubuntu 6.06 (dapper)
Version: GNOME2.14.3 unspecified
Gnome-Distributor: Ubuntu

Once in a while the calendar crashes after I attempt to save the change