Thanks, i'm the system administrator too... but that only happened to me!!
I've fixed the problem changing $allow_thread_sort to false!!
in config.php i've only have changed to false $allow_server_sort, didn't
know that thread chould be changed too... but now it's fixed!!
Thanks for helping ;)
when i try to login to my account i get this message:
ERROR:
ERROR: Bad or malformed request.
Query: THREAD REFERENCES ISO-8859-1 ALL
Server responded: unknown command
i've searched for a solution but i can't find one!
it's only in inbox folder... and only with my account!
Somebody here can help