1.5.1 ffmpeg does not compile even though x264 is compiled

[vipopat01@as11 ffmpeg]$ ./configure --enable-gpl --enable-libfaac --enable-libmp3lame --enable-libtheora --enable-libvorbis --enable-libx264 --enable-nonfree --enable-postproc --enable-version3 --enable-x11grab --enable-libvpx --enable-librtmp --enable-libxvid
ERROR: libx264 not found

If you think configure made a mistake, make sure you are using the latest
version from Git. If the latest version fails, report the problem to the
ffmpeg-user@ffmpeg.org mailing list or IRC #ffmpeg on irc.freenode.net.
Include the log file "config.log" produced by configure as this will help
solve the problem.
[vipopat01@as11 ffmpeg]$ ll /usr/lib
lib/ lib64/ libexec/
[vipopat01@as11 ffmpeg]$ ll /usr/lib/libx264.a
arch.mak compat/ COPYING.LGPLv3 ffmpeg_opt.c ffserver_config.h libavutil/ Makefile version.sh
Changelog config.fate CREDITS ffmpeg_vda.c INSTALL.md libpostproc/ presets/
cmdutils.c config.log doc/ ffmpeg_vdpau.c libavcodec/ library.mak README.md
cmdutils_common_opts.h configure ffmpeg.c ffplay.c libavdevice/ libswresample/ RELEASE
cmdutils.h COPYING.GPLv2 ffmpeg_dxva2.c ffprobe.c libavfilter/ libswscale/ RELEASE_NOTES
cmdutils_opencl.c COPYING.GPLv3 ffmpeg_filter.c ffserver.c libavformat/ LICENSE.md tests/
common.mak COPYING.LGPLv2.1 ffmpeg.h ffserver_config.c libavresample/ MAINTAINERS tools/
[vipopat01@as11 ffmpeg]$ ll /usr/lib/libx264.a


Can someone please let me know what could be the issue

[vipopat01@as11 ffmpeg]$ uname -a
Linux as11.cs.quadriga.com 2.6.32-504.el6.x86_64 #1 SMP Wed Oct 15 04:27:16 UTC 2014 x86_64 x86_64 x86_64 GNU/Linux
[vipopat01@as11 ffmpeg]$

[zip]

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