missing a plug-in

01 dec 2012, 13:58:35: Tracker-Warning **: Call to gst_discoverer_discover_uri() failed: Your GStreamer installation is missing a plug-in.
01 dec 2012, 13:58:35: Tracker: No extractor or failed
01 dec 2012, 13:58:35: Tracker: Dispatching 'file:///home/forage/Pictures/dolpOrSexy.0.jpg' in main thread
01 dec 2012, 13:58:35: Tracker: Extracting...
01 dec 2012, 13:58:35: Tracker:   Using /usr/lib/tracker-0.14/extract-modules/libextract-jpeg.so...
01 dec 2012, 13:58:35: Tracker: Done (9 items)
01 dec 2012, 13:58:35: Tracker: Dispatching 'file:///home/forage/Pictures/Anti-Audentis.psd' in main thread
01 dec 2012, 13:58:35: Tracker: Extracting...
01 dec 2012, 13:58:35: Tracker:   Using /usr/lib/tracker-0.14/extract-modules/libextract-gstreamer.so...
01 dec 2012, 13:58:35: Tracker: GStreamer backend in use:
01 dec 2012, 13:58:35: Tracker:   Discoverer/GUPnP-DLNA
01 dec 2012, 13:58:35: Tracker: ---> [27926|0] Success, no error given
01 dec 2012, 13:58:35: Tracker: <--- [27935|0] handle_method_call_get_metadata_fast (uri:'file:///home/forage/Pictures/Ireland%202008/DSCN0157.jpg', mime:'image/jpeg', index_fd:0)

01 dec 2012, 13:58:35: Tracker-Warning **: Call to gst_discoverer_discover_uri() failed: Your GStreamer installation is missing a plug-in.
01 dec 2012, 13:58:35: Tracker: No extractor or failed
01 dec 2012, 13:58:35: Tracker: Dispatching 'file:///home/forage/Pictures/aglite80.jpg' in main thread
01 dec 2012, 13:58:35: Tracker: Extracting...
01 dec 2012, 13:58:35: Tracker:   Using /usr/lib/tracker-0.14/extract-modules/libextract-jpeg.so...
01 dec 2012, 13:58:35: Tracker: Done (7 items)
01 dec 2012, 13:58:35: Tracker: Dispatching 'file:///home/forage/Pictures/ff3.jpg' in main thread
01 dec 2012, 13:58:35: Tracker: Extracting...
01 dec 2012, 13:58:35: Tracker:   Using /usr/lib/tracker-0.14/extract-modules/libextract-jpeg.so...
01 dec 2012, 13:58:35: Tracker: ---> [27928|0] Success, no error given
01 dec 2012, 13:58:35: Tracker: Done (6 items)