Mine

dementual@dementual-laptop:~/Desktop$ sudo mencoder in.rmvb -oac mp3lame -lameopts preset=128 -ovc lavc -lavcopts vcodec=mpeg4:vbitrate=1200 -ofps 25 -of avi -o out.avi
MEncoder 2:1.0~rc1-0ubuntu13 (C) 2000-2006 MPlayer Team
CPU: Intel(R) Celeron(R) M CPU        520  @ 1.60GHz (Family: 6, Model: 15, Stepping: 6)
CPUflags: Type: 6 MMX: 1 MMX2: 1 3DNow: 0 3DNow2: 0 SSE: 1 SSE2: 1
Compiled with runtime CPU detection.
success: format: 0  data: 0x0 - 0x4ec079b
REAL file format detected.
Stream description: Video Stream
Stream mimetype: video/x-pn-realvideo
Stream description: Audio Stream
Stream mimetype: audio/x-pn-realaudio
Stream mimetype: logical-fileinfo
VIDEO:  [RV40]  640x480  24bpp  30.000 fps    0.0 kbps ( 0.0 kbyte/s)
[V] filefmt:11  fourcc:0x30345652  size:640x480  fps:30.00  ftime:=0.0333
==========================================================================
Opening audio decoder: [ffmpeg] FFmpeg/libavcodec audio decoders
AUDIO: 44100 Hz, 2 ch, s16le, 96.5 kbit/6.84% (ratio: 12058->176400)
Selected audio codec: [ffcook] afm: ffmpeg (FFmpeg COOK audio decoder)
==========================================================================
Opening video filter: [expand osd=1]
Expand: -1 x -1, -1 ; -1, osd: 1, aspect: 0.000000, round: 1
==========================================================================
Opening video decoder: [realvid] RealVideo decoder
Error: /usr/lib/win32/drvc.so: cannot open shared object file: No such file or directory
Win32 LoadLibrary failed to load: drvc.so, /usr/lib/win32/drvc.so, /usr/local/lib/win32/drvc.so
Error loading dll
ERROR: Could not open required DirectShow codec drvc.so.
Read the RealVideo section of the DOCS!
VDecoder init failed :(
Opening video decoder: [realvid] RealVideo decoder
Error: /usr/lib/win32/drv4.so.6.0: cannot open shared object file: No such file or directory
Win32 LoadLibrary failed to load: drv4.so.6.0, /usr/lib/win32/drv4.so.6.0, /usr/local/lib/win32/drv4.so.6.0
Error loading dll
ERROR: Could not open required DirectShow codec drv4.so.6.0.
Read the RealVideo section of the DOCS!
VDecoder init failed :(
Opening video decoder: [realvid] RealVideo decoder
Win32 LoadLibrary failed to load: drv43260.dll, /usr/lib/win32/drv43260.dll, /usr/local/lib/win32/drv43260.dll
Error loading dll
ERROR: Could not open required DirectShow codec drv43260.dll.
Read the RealVideo section of the DOCS!
VDecoder init failed :(
Opening video decoder: [realvid] RealVideo decoder
Error: /usr/lib/win32/drvc.bundle/Contents/MacOS/drvc: cannot open shared object file: No such file or directory
Win32 LoadLibrary failed to load: drvc.bundle/Contents/MacOS/drvc, /usr/lib/win32/drvc.bundle/Contents/MacOS/drvc, /usr/local/lib/win32/drvc.bundle/Contents/MacOS/drvc
Error loading dll
ERROR: Could not open required DirectShow codec drvc.bundle/Contents/MacOS/drvc.
Read the RealVideo section of the DOCS!
VDecoder init failed :(
Cannot find codec matching selected -vo and video format 0x30345652.
Read DOCS/HTML/en/codecs.html!
==========================================================================

Exiting...
dementual@dementual-laptop:~/Desktop$