Cannot export videos

I am not able to export videos from openshot, in any format I have tried. This is without any editing at all; just trying to save in a different format. After filling out the export box (I have tried several combinations of settings) and pressing "Export", the box just greys and sits there, until I kill it (I have waited up to half an hour). The video file is created, but trying to play it gives only a flash of black screen. There is no error message. If I start openshot from a terminal, here is the output I get:

--------------------------------
   OpenShot (version 1.2.2)
--------------------------------
Process no longer exists: 22559. Creating new pid lock file.
state saved
on_mnuImportFiles_activate called with self.GtkImageMenuItem
project modified: Added file
state saved
on_tlbPlay_clicked called with self.GtkToolButton
on_tlbPlay_clicked called with self.GtkToolButton
project modified: Removed file
state saved
on_mnuImportFiles_activate called with self.GtkImageMenuItem
project modified: Added file
state saved
on_tlbPlay_clicked called with self.GtkToolButton
on_treeFiles_row_activated
on_mnuPreview_activate
on_tlbPlay_clicked called with self.GtkToolButton
on_mnuMakeMovie1_activate called with self.GtkImageMenuItem
on_tlbMakeMovie_clicked called with self.GtkImageMenuItem
on_cboProjectType_changed
on_cboExportTo_changed
on_btnExportVideo_clicked
on_frmExportVideo_destroy
----------------------------------------------
The destroy command happens when I close the export window. There are no error messages.

This is: kUbuntu-10.10, 64-bit
libavformat-unstripped-52, libavformat-extra-52, and libavcodec-unstripped-52 are installed.
openshot version 1.2.2 (from ubuntu repositories)

greenman@Wolfenstein:~$ melt -query "producers"
---
producers:
  - abnormal
  - color
  - colour
  - consumer
  - loader
  - hold
  - noise
  - ppm
  - vorbis
  - kino
  - frei0r.ising0r
  - frei0r.lissajous0r
  - frei0r.nois0r
  - frei0r.onecol0r
  - frei0r.partik0l
  - frei0r.plasma
  - xml
  - xml-string
  - slowmotion
  - libdv
  - pgm
  - pango
  - pixbuf
  - qimage
  - kdenlivetitle
  - avformat
  - avformat-novalidate
  - framebuffer
  - melt
  - melt_file
...
greenman@Wolfenstein:~$ ffmpeg -i
FFmpeg version 0.6-4:0.6-2ubuntu6, Copyright (c) 2000-2010 the FFmpeg developers
  built on Oct 5 2010 22:36:53 with gcc 4.4.5
(snip)
libavutil 50.15. 1 / 50.15. 1
  libavcodec 52.72. 2 / 52.72. 2
  libavformat 52.64. 2 / 52.64. 2
  libavdevice 52. 2. 0 / 52. 2. 0
  libavfilter 1.19. 0 / 1.19. 0
  libswscale 0.11. 0 / 0.11. 0
  libpostproc 51. 2. 0 / 51. 2. 0