MPEG file is not played

I click preview button on media manager with mpeg item selected, it did not display the movie.
After that, some function seems working but OpenLP cannot stop with no message.
I hit ctrl+C, this error occur.

The detailed step is:
1. add mpeg file to media.
2. restart OpenLP (I'm not sure but this step is not required to reproduce)
3. click the entry of the mpeg file in media plugin
4. click preview button (live, add buttons also malfunction)
-- in this step no movie appears (attached screenshot)

I tried 3 times, I will copy 3 tracebacks.
The version of bug report below is 1.9.2-bzr987,
but actually I got with
$ bzr clone http://bazaar.launchpad.net/~openlp-core/openlp/trunk/
and last log is:
------------------------------------------------------------
revno: 1391 [merge]
branch nick: openlp
timestamp: Tue 2011-03-15 19:23:05 +0000
message:
  Alert position, genearl import, Windows QPaint error, case insensitive song order and presentation issues
------------------------------------------------------------

Thanks.

**OpenLP Bug Report**
Version: 1.9.2-bzr987 ### incorrect version

--- Details of the Exception. ---

I click preview on media manager with mpeg item selected, it did not display the movie.
After that I hit ctrl+C, this error occur.

 --- Exception Traceback ---
Traceback (most recent call last):
  File "/home/kamae/openlp/trunk/openlp/core/lib/mediamanageritem.py", line 425, in onPreviewClick
    serviceItem = self.buildServiceItem()
  File "/home/kamae/openlp/trunk/openlp/core/lib/mediamanageritem.py", line 505, in buildServiceItem
    if self.generateSlideData(serviceItem, item, xmlVersion):
  File "/home/kamae/openlp/trunk/openlp/plugins/media/lib/mediaitem.py", line 141, in generateSlideData
    Receiver.send_message(u'openlp_process_events')
  File "/home/kamae/openlp/trunk/openlp/core/lib/eventreceiver.py", line 283, in send_message
    Receiver.eventreceiver.send_message(event, msg)
  File "/home/kamae/openlp/trunk/openlp/core/lib/eventreceiver.py", line 250, in send_message
    self.emit(QtCore.SIGNAL(event), msg)
KeyboardInterrupt

 --- Exception Traceback ---
Traceback (most recent call last):
  File "/home/kamae/openlp/trunk/openlp/core/lib/mediamanageritem.py", line 425, in onPreviewClick
    serviceItem = self.buildServiceItem()
  File "/home/kamae/openlp/trunk/openlp/core/lib/mediamanageritem.py", line 505, in buildServiceItem
    if self.generateSlideData(serviceItem, item, xmlVersion):
  File "/home/kamae/openlp/trunk/openlp/plugins/media/lib/mediaitem.py", line 141, in generateSlideData
    Receiver.send_message(u'openlp_process_events')
  File "/home/kamae/openlp/trunk/openlp/core/lib/eventreceiver.py", line 283, in send_message
    Receiver.eventreceiver.send_message(event, msg)
  File "/home/kamae/openlp/trunk/openlp/core/lib/eventreceiver.py", line 249, in send_message
    log.debug(u'Event %s passed with payload %s' % (event, msg))
KeyboardInterrupt

 --- Exception Traceback ---
Traceback (most recent call last):
  File "/home/kamae/openlp/trunk/openlp/core/lib/mediamanageritem.py", line 425, in onPreviewClick
    serviceItem = self.buildServiceItem()
  File "/home/kamae/openlp/trunk/openlp/core/lib/mediamanageritem.py", line 505, in buildServiceItem
    if self.generateSlideData(serviceItem, item, xmlVersion):
  File "/home/kamae/openlp/trunk/openlp/plugins/media/lib/mediaitem.py", line 141, in generateSlideData
    Receiver.send_message(u'openlp_process_events')
  File "/home/kamae/openlp/trunk/openlp/core/lib/eventreceiver.py", line 283, in send_message
    Receiver.eventreceiver.send_message(event, msg)
  File "/home/kamae/openlp/trunk/openlp/core/lib/eventreceiver.py", line 250, in send_message
    self.emit(QtCore.SIGNAL(event), msg)
KeyboardInterrupt

--- System information ---
Platform: Linux-2.6.35.11-83.fc14.x86_64-x86_64-with-fedora-14-Laughlin

--- Library Versions ---
Python: 2.7.0
Qt4: 4.7.1
Phonon: 4.4.3
PyQt4: 4.7.4
SQLAlchemy: 0.6.6
BeautifulSoup: 3.2.0
lxml: 2.2.8
Chardet: 2.0.1
PyEnchant: 1.3.1
PySQLite: -