In the preferences if you select display Time, Message Size, send type, then the inbox folder is sorted descending (upside down)by default.
I had emails form 6/10/2004 ~ 6/16/2004 in the inbox and everything was sorted ok, i.e 6/16/200 mail was on the top, but once I changed the preferences to display those 3 columns the view is sorted the other way i.e. 6/10/2004 mail is showing on the top.
I fixed this in my Db but it wil be great if you can fix it on the template as well.
thanks