Remember to cover the basics, that is, what you expected to happen and
what in fact did happen.  You don't know how to make a good report?  See

     http://orgmode.org/manual/Feedback.html#Feedback

Your bug report will be posted to the Org-mode mailing list.
------------------------------------------------------------------------

When `org-previous-item' is called on an item with nothing above it
Orgmode enters an infinite loop. The reason is that
`org-previous-item' searches for non-empty lines by moving point up
line by line and if there is nothing above an item point gets stuck on
begin of buffer.

example.org
,----
| 
|  - Item
`----

Move point on Item, M-x org-previous-item RET and Orgmode enters the
infinite loop.

Attached patch adds a conditional clause to `org-previous-item' that
leaves the search loop if point reaches beginning of buffer.

Emacs  : GNU Emacs 23.1.50.1 (i486-pc-linux-gnu, GTK+ Version 2.18.3)
 of 2009-11-28 on elegiac, modified by Debian
Package: Org-mode version 6.33trans (release_6.33f.80.gb777e3)