Description of Problem:
Renaming a vfolder with subfolders sometimes
leaves the folder structure in inconsistent state
- see below. I tested it on vfolders, haven't
tried if it happens with plain folders too.

Steps to reproduce the problem:
1. Create a vfolder called "aa" (contents don't
matter, e.g. just select to take data from all
folders to make the dialog happy).
2. Create its subfolder called "bb".
3. Rename "aa" to "aaa".
4. Delete "bb".
5. Delete "aaa".
6. Close Evolution and start it again.

Actual Results:
A ghost of the vfolder "aa" with its subfolder is
suddenly back. Evolution says it can't show its
contents. Deleting it (after deleting its
subfolder) doesn't have a visible effect, although
it does disappear when I restart Evolution yet
again. Some files with names of these folders are
left in ~/evolution.

Expected Results:
Renaming a folder with subfolders should leave no
trails of the old name.

How often does this happen? 
Always when renaming a folder with subfolders.

Additional Information: