[MPlayer-users] fixed-point AMR-nb compile error

[qwen dux]

hi,
I would like to compile mplayer with support for 3gp/AMR(fixed-point) 
files, I tried it as follows:
Downloaded the fixed-point amr codec sources from
http://www.3gpp.org/ftp/Specs/archiv.../26073-510.zip and extracted it
to $Mplayer/libavcodec/amr

and with the following commands:
./configure --disable-mencoder --disable-amr_nb
but Make exits with the following errors:
libavcodec/libavcodec.a(amr.o): In function
`amr_nb_decode_frame':amr.c:(.text+0x2c4): undefined reference to
`UnpackBits'
libavcodec/libavcodec.a(amr.o): In function
`amr_nb_encode_frame':amr.c:(.text+0x479): undefined reference to
`PackBits'
collect2: ld returned 1 exit status
make: *** [mplayer] Error 1

but I complied float-point amr-nb normally,What am I doing wrong?