It seems to be an openGL bug.
The display is initialised well.
kdenlive: Mlt inited
kdenlive: Creating new document
kdenlive: deleting contents...
kdenlive: **************** INIT DOCUMENT VIEW ***************
kdenlive: Mlt inited
QApplication::postEvent: Unexpected null receiver
QApplication::postEvent: Unexpected null receiver
kdenlive: **************** INIT DOCUMENT VIEW 1***************
kdenlive: ++ FOUND CLIP
kdenlive: WARNING: Got a request for a changed clip that is not in the document : VID0011.AVI
kdenlive: *** DOCUMENT adding clip: VID0011.AVI
kdenlive: ++++++++++++ DOC SELECT NEW ITEM: 0
Launched ok, pid = 15356
kdenlive: WARNING: Opening url /home/jmpoure/reportages/2007/20070525 - Vexin, part 2/projet.kdenlive
kdenlive: WARNING: KdenliveDoc::loadFromXML() document element has unknown tagName : kdenlivedoc
OggS-SEEK: at 0 want 78328 got 68160 (diff-requested 78328)
OggS-SEEK: at 78400 want 520 got 0 (diff-requested -77880)
kdenlive: Mlt inited
kdenlive: Mlt inited
kdenlive: Creating new document
kdenlive: deleting contents...
kdenlive: **************** INIT DOCUMENT VIEW ***************
Xlib: unexpected async reply (sequence 0x61)!
KCrash: Application 'kdenlive' crashing...

Sure, thanks.