git diff configure.ac 
diff --git a/configure.ac b/configure.ac
index b74fb47..1a5a82e 100644
--- a/configure.ac
+++ b/configure.ac
@@ -320,6 +320,9 @@ AC_ARG_ENABLE(force-sendpacket,
     AC_HELP_STRING([--enable-force-sendpacket], [Force using libpcap's pcap_sendpacket() for sending packets]),
     [ AC_DEFINE([FORCE_INJECT_PCAP_SENDPACKET], [1], [Force using libpcap's pcap_sendpacket() for sending packets])])

+force_pcap=no
+AC_ARG_ENABLE(force_pcap, AC_HELP_STRING([--enable-force_pcap], [Force libpcap usage]))
+
 dnl Dynamic link libraries
 dynamic_link=no
 AC_ARG_ENABLE(dynamic-link,
@@ -374,6 +377,7 @@ AC_ARG_WITH(libpcap,
     AC_HELP_STRING([--with-libpcap=DIR], 
         [Use libpcap in DIR]),
 [
+    force_pcap=yes
     trypcapdir=$withval
     for testdir in ${withval} ${withval}/include ; do
            if test -f "${testdir}/pcap.h" -a $foundpcap = no ; then
@@ -896,6 +900,7 @@ if test "$have_netmap" != no ; then
 fi
 CPPFLAGS="$OLDCPPFLAGS"

+if test "${force_pcap}" = "no"; then :
 have_pf=no
 dnl Check for linux PF_PACKET support
 AC_MSG_CHECKING(for PF_PACKET socket sending support)
@@ -983,6 +988,7 @@ if test $have_bpf = yes ; then
     AC_DEFINE([HAVE_BPF], [1], 
             [Do we have BPF device support?])
 fi
+fi

 dnl ##################################################
 dnl # Check for libdnet, but only if not Cygwin! 

How to compile tcpreply with PF_RING
------------------------------------

1. Download and compile PF_RING. We assume that you have stored
   into /home/user/ (i.e. /home/user/PF_RING/....)

2. Create a "fat" libpcap library that contains both the pcap and pf_ring library
   cd /home/user/PF_RING/userland/libpcap
   ./mkFatLibpcap.sh

3. Make sure you have installed the libnl-dev required by libpcap.
   Example on Ubuntu/Debian do: apt-get install libnl-dev

4. In your tcpreplay directory do
   ./autogen.sh 
   ./configure --with-libpcap=/home/user/PF_RING/userland/libpcap-1.1.1-ring/

cd PF_RING/userland/libpcap
make 
make install

checking for numa_available in -lnuma... yes
checking for pthread_create in -lpthread... yes
checking for library containing pcap_get_pfring_id... no
checking for library containing pcap_close... no
configure: error: Unable to link libpcap in /usr/local