What are the specifications of Flex usable FLV videos?

I have a server which streams FLV files to a Flex client. In this flex client, the video timeline advances incoherently, and no video can be seen on screen (only the sound can be heard).

My FLV file has been generated using ffmpeg, which says (about this generated file)

FFmpeg version 0.6, Copyright (c) 2000-2010 the FFmpeg developers
  built on Aug  8 2010 04:24:04 with gcc 4.3.2
  configuration: --prefix=/home/marpada/ffmpegfull --enable-gpl --enable-version3 --enable-nonfree --disable-ffplay --disable-ffserver --enable-libmp3lame --enable-libfaac --enable-libvpx --enable-libfaad --enable-libvorbis --enable-libopencore-amrnb --enable-libopencore-amrwb --enable-libxvid --enable-libx264 --enable-libtheora --extra-ldflags=-static --extra-libs='-lvorbis -logg -lxvidcore -lx264 -lopencore-amrnb -lopencore-amrwb -lfaad -lfaac -lvpx -ltheora -lm -lpthread' --enable-small --enable-runtime-cpudetect
  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
  libswscale     0.11. 0 /  0.11. 0
[flv @ 0x95c6aa0]Estimating duration from bitrate, this may be inaccurate

Seems stream 0 codec frame rate differs from container frame rate: 1000.00 (1000/1) -> 25.00 (25/1)
Input #0, flv, from '/appli/perigee_70ri/data/files/ged_bur%0/Imagettes/70ri/279/2/8/20_109021138o.70ri_FLV_preview_.flv':
  Metadata:
    hasMetadata     : true
    hasVideo        : true
    hasAudio        : true
    duration        : 589
    lasttimestamp   : 589
    lastkeyframetimestamp: 589
    width           : 352
    height          : 288
    videodatarate   : 199
    framerate       : 25
    audiodatarate   : 12开发者_开发技巧5
    audiosamplerate : 44100
    audiosamplesize : 16
    stereo          : true
    filesize        : 25058444
    videosize       : 15195503
    audiosize       : 9690850
    datasize        : 23027
    metadatacreator : flvmeta 1.1-r202
    audiocodecid    : 2
    videocodecid    : 2
    audiodelay      : 0
    canSeekToEnd    : false
    hasCuePoints    : false
    hasKeyframes    : true
  Duration: 00:09:48.78, start: 0.000000, bitrate: 332 kb/s
    Stream #0.0: Video: flv, yuv420p, 352x288, 204 kb/s, 25 tbr, 1k tbn, 1k tbc
    Stream #0.1: Audio: mp3, 44100 Hz, 2 channels, s16, 128 kb/s
At least one output file must be specified

Which, as far as it seems to me, is OK.

Furthermore, the video plays nice in VLC.

Use H.264 for the video stream.