As you mentioned your email reconciliation is on and this function should be fine with your software versions.
You would likely want to re create the state database Mail Folders.
1. Turn email reconciliation off on the BlackBerry smartphone.
2. Open users state database on the BES, go into the mail folders view on the left and delete contents.
3. Turn email reconciliation back on the BlackBerry smartphone and test after you see the Mail folders view of state database populate again, best to test with a new message.