Description of problem:
evo seems to want to push unread messages to the top, moving read messages below unread messages.


Version-Release number of selected component (if applicable):
evolution-2.24.0-2.fc10.x86_64


How reproducible:
every time


Steps to Reproduce:
1. goto folder w/ unread messages
2. select 1st unread message
3. goto different folder and back again
  
Actual results:
read message will now appear at bottom, below all unread messages


Expected results:
sorting doesn't change


Additional info:
* leave as default sort (ie. don't click any column headers)

I've also seen some strange sorting behavior in folders w/ mailing list archives which seems likely related.

I'll attach 3 screenshots:
- ss1.png == all unread
- ss2.png == 1st message read, others left unread
- ss3.png == messages re-ordered
***reproduction step #3 was performed between ss2.png and ss3.png***