CentOS 5.1 Linphone installation:

1. Install libraries: ( I used to put sources in /usr/local/src )
  - speex
  - libosip2
  - libeXosip2
  - msilbc (Part I. source)
  - ffmpeg (Check it out from SVN)
  svn checkout svn://svn.mplayerhq.hu/ffmpeg/trunk ffmpeg

2. Install CentOS add-on libraries: (Linphone2SDL_CentOS51RPMs.zip)
  (To have SDL to support video feature)
  - rpm -ivh *.rpm

3. Install Linphone (under /bin/bash):
  > export PKG_CONFIG_PATH=/usr/local/lib/pkgconfig
  > cd linphone-2.1.1
  > ./configure --prefix=/usr/local --enable-alsa --enable-video --with-ffmpeg=/usr/local --with-speex=/usr/local
  > make
  > make install

4. Install msilbc plugin:
  > cd msilbc-2.0.0
  > export LINPHONE_BUILD=/usr/local/src/linphone-2.1.1

  (Patch ilbc.c to remove the line with "MS_FILTER_SET_FMTP")

  > make
  > make install

5. Run linphonec:
  > /usr/local/bin/linphonec