rtspsrc plays nothing?

[Paolo Bolzoni]

I tried with version 0.10, but I have still some problems.
I can get the rtsp stream and depay it, here is the command line:

$ gst-launch-0.10 -tev   rtspsrc protocols=4 buffer-mode=0 name=src
location='rtsp://128.2.10.151:80/004/MLtalk2_10-17.mov' latency=1000
src. ! 'application/x-rtp' ! rtpmp4gdepay ! fakesink silent=true  src.
! 'application/x-rtp' ! rtph264depay ! fakesink silent=true | grep
fakesink

/GstPipeline:pipeline0/GstFakeSink:fakesink1.GstPad:sink: caps =
video/x-h264, stream-format=(string)byte-stream, alignment=(string)nal
/GstPipeline:pipeline0/GstFakeSink:fakesink0.GstPad:sink: caps =
audio/mpeg, mpegversion=(int)4, stream-format=(string)raw,
codec_data=(buffer)1188

I filtered the output to see only the caps of the fakesinks. For what
I understood they should be acceptable
for matroska muxing. But, this second command fails:

$ gst-launch-0.10 -e matroskamux name=mux  rtspsrc protocols=4
buffer-mode=0 name=src
location='rtsp://128.2.10.151:80/004/MLtalk2_10-17.mov' latency=1000
src. ! 'application/x-rtp' ! rtpmp4gdepay ! mux.  src. !
'application/x-rtp' ! rtph264depay ! mux. mux. ! filesink
location=video.mkv
[...]
ERROR: from element /GstPipeline:pipeline0/GstRTSPSrc:src: Internal
data flow error.
Additional debug info:
gstrtspsrc.c(4184): gst_rtspsrc_loop (): /GstPipeline:pipeline0/GstRTSPSrc:src:
streaming task paused, reason not-negotiated (-4)
[...]

I am starting to be a little confused, what is wrong this time?

Thanks,
Paolo