Folders with unread mail inside are prefixed by folder-display|

Description of the problem:
A folder which has unread mail inside it will be prefixed by the phrase "folder-display|" within the sidebar. This did not happen in the Dapper version of Edgy but is seemingly only a cosmetic issue.

Steps to reproduce:
1. Start evolution .
2. Make sure the Mail button is selected in the sidebar.
3. Click on Inbox.
(If Inbox is not named "folder-display|Inbox")
4. Click on the "Welcome to Evolution!" message to select it. Wait a few seconds for it to be marked as read.
5. Press Ctrl-Shift-K to mark the mail as unread.

Expected results:
Inbox to be bold within the sidebar and to still be called Inbox.

Actual results:
Inbox becomes bold and is also renamed to folder-display|Inbox .

Version information:
(Edgy)
evolution 2.8.1-0ubuntu4

Additional information:
Happens with a clean profile too.