[root@c27016-p20786 ffmpeg-0.8.6]# nice -n 19 ./ffmpeg  -i 'kb1_0.mp4' -s 658x362 -vf "pad=658:490:0:64" -r 15 -b 250 -ar 22050 -ab 48 'test.flv'
ffmpeg version 0.8.6, Copyright (c) 2000-2011 the FFmpeg developers
  built on Dec  1 2011 10:11:45 with gcc 4.1.2 20080704 (Red Hat 4.1.2-51)
  configuration: --enable-debug --enable-version3 --enable-shared --enable-gpl --enable-postproc --enable-nonfree --enable-avfilter --enable-pthreads --extra-cflags=-fPIC
  libavutil    51.  9. 1 / 51.  9. 1
  libavcodec   53.  7. 0 / 53.  7. 0
  libavformat  53.  4. 0 / 53.  4. 0
  libavdevice  53.  1. 1 / 53.  1. 1
  libavfilter   2. 23. 0 /  2. 23. 0
  libswscale    2.  0. 0 /  2.  0. 0
  libpostproc  51.  2. 0 / 51.  2. 0

Seems stream 0 codec frame rate differs from container frame rate: 180000.00 (180000/1) -> 90000.00 (180000/2)
Input #0, mov,mp4,m4a,3gp,3g2,mj2, from 'kb1_0.mp4':
  Metadata:
    major_brand     : mp42
    minor_version   : 0
    compatible_brands: mp42isomavc1
    creation_time   : 2011-10-13 00:29:27
    encoder         : HandBrake 0.9.5 2011010300
  Duration: 00:30:44.89, start: 0.000000, bitrate: 1184 kb/s
    Stream #0.0(und): Video: h264 (Main), yuv420p, 320x176, 999 kb/s, 30 fps, 90k tbr, 90k tbn, 180k tbc
    Metadata:
      creation_time   : 2011-10-13 00:29:27
    Stream #0.1(eng): Audio: aac, 48000 Hz, stereo, s16, 177 kb/s
    Metadata:
      creation_time   : 2011-10-13 00:29:27
WARNING: The bitrate parameter is set too low. It takes bits/s as argument, not kbits/s
WARNING: The bitrate parameter is set too low. It takes bits/s as argument, not kbits/s
[buffer @ 0x9ae07e0] w:320 h:176 pixfmt:yuv420p tb:1/1000000 sar:0/1 sws_param:
[scale @ 0x9ae1de0] w:320 h:176 fmt:yuv420p -> w:658 h:362 fmt:yuv420p flags:0x4
[pad @ 0x9ae2340] w:658 h:362 -> w:658 h:490 x:0 y:64 color:0x108080FF[yuva]
Output #0, flv, to 'test.flv':
  Metadata:
    major_brand     : mp42
    minor_version   : 0
    compatible_brands: mp42isomavc1
    creation_time   : 2011-10-13 00:29:27
    encoder         : Lavf53.4.0
    Stream #0.0(und): Video: flv, yuv420p, 658x490, q=2-31, 0 kb/s, 1k tbn, 15 tbc
    Metadata:
      creation_time   : 2011-10-13 00:29:27
    Stream #0.1(eng): Audio: adpcm_swf, 22050 Hz, stereo, s16, 0 kb/s
    Metadata:
      creation_time   : 2011-10-13 00:29:27
Stream mapping:
  Stream #0.0 -> #0.0
  Stream #0.1 -> #0.1
Press [q] to stop, [?] for help
[aac @ 0x9ae2b00] Number of bands (54) exceeds limit (46).3 bitrate= 352.5kbits/s dup=0 drop=18042
Error while decoding stream #0.1
[aac @ 0x9ae2b00] TNS filter order 13 is greater than maximum 12.
Error while decoding stream #0.1
frame=27674 fps=178 q=31.0 Lsize=   79246kB time=00:30:44.82 bitrate= 351.9kbits/s dup=0 drop=27671
video:38273kB audio:39919kB global headers:0kB muxing overhead 1.347360%