FLV4 video - which codec do I need?

[john wendel]

I've got an FLV4 encoded video that I'd like to watch. Mplayer says

> [mkv] Track ID 1: video (V_MS/VFW/FOURCC), -vid 0
> [mkv] Track ID 2: audio (A_MPEG/L3), -aid 0, -alang jpn
> [mkv] Track ID 3: subtitles (S_TEXT/ASS), -sid 0, -slang eng
> [mkv] Will play video track 1.
> Matroska file format detected.
> VIDEO:  [FLV4]  640x368  0bpp  25.000 fps    0.0 kbps ( 0.0 kbyte/s)
> [vdpau] Error when calling vdp_device_create_x11: 1
> ==========================================================================
> Cannot find codec matching selected -vo and video format 0x34564C46.
> ==========================================================================

I downloaded and installed the "all" codec pack from the mplayer 
website, didn't help.

Any clues appreciated.

Thanks,

John