--- Libnet-1.0.2a.orig/acinclude.m4	2000-12-12 19:31:54.000000000 +0100
+++ Libnet-1.0.2a/acinclude.m4	2009-06-12 21:48:27.000000000 +0200
@@ -30,65 +30,43 @@ AC_DEFUN(AC_LIBNET_CHECK_PF_PACKET,
         *)
 
     cat > pf_packet-test.c << EOF
-#include <net/if.h>
-#if (__GLIBC__)
-#include <netinet/if_ether.h>
-#include <net/if_arp.h>
+#include <stdio.h>
+#include <errno.h>
+#include <stdlib.h>
+#include <netinet/in.h>
+#include <sys/socket.h>
+#include <features.h>    /* for the glibc version number */
+#if __GLIBC__ >= 2 && __GLIBC_MINOR >= 1
+#include <netpacket/packet.h>
+#include <net/ethernet.h>     /* the L2 protocols */
 #else
-#include <linux/if_arp.h>
-#include <linux/if_ether.h>
+#include <asm/types.h>
+#include <linux/if_packet.h>
+#include <linux/if_ether.h>   /* The L2 protocols */
 #endif
-#if (PF_PACKET)
+
 #ifndef SOL_PACKET
 #define SOL_PACKET 263
 #endif  /* SOL_PACKET */
-#include <linux/if_packet.h>
-#endif
-#include "./include/libnet.h"
 
 int
 main()
 {
-#if (PF_PACKET)
     int fd;
-    struct sockaddr_ll sa;
-    struct ifreq ifr;
-    struct packet_mreq mr;
-    char *device ="lo";
 
     fd = socket(PF_PACKET, SOCK_RAW, htons(ETH_P_ALL));
     if (fd == -1)
     {
-        printf("choked");
-        exit (EXIT_FAILURE);
-    }
-
-    memset(&sa, 0, sizeof(sa));
-    strcpy(ifr.ifr_name, device);
-    if (ioctl(fd, SIOCGIFINDEX, &ifr) < 0)
-    {
-        printf("choked");
-        exit (EXIT_FAILURE);
-    }
-    sa.sll_family = AF_PACKET;
-    sa.sll_ifindex = ifr.ifr_ifindex;
-    sa.sll_protocol = htons(ETH_P_ALL);
-
-    memset(&mr, 0, sizeof (mr));
-    mr.mr_ifindex = sa.sll_ifindex;
-    mr.mr_type = PACKET_MR_ALLMULTI;
-
-    if (setsockopt(fd, SOL_PACKET, PACKET_ADD_MEMBERSHIP, (char *)&mr,
-            sizeof (mr)) < 0)
-    {
-        printf("choked\n");
+        if (errno == EPERM)
+        {
+            /* user's UID != 0 */
+            printf("probably");
+            exit (EXIT_FAILURE);
+        }
+        printf("no");
         exit (EXIT_FAILURE);
     }
-    /* yay.  we made it and it workz! */
     printf("yes");
-#else   /* PF_PACKET */
-    printf("no");
-#endif
     exit (EXIT_SUCCESS);
 }
 EOF
@@ -104,16 +82,21 @@ EOF
     if test $ac_libnet_have_pf_packet = choked; then
         AC_MSG_RESULT(test program choked... assuming no)
     elif test $ac_libnet_have_pf_packet = yes; then
-        AC_DEFINE(HAVE_PF_PACKET)
+        AC_MSG_RESULT(yes)
         LIBNET_CONFIG_DEFINES="$LIBNET_CONFIG_DEFINES -DHAVE_PF_PACKET"
+    elif test $ac_libnet_have_pf_packet = probably; then
+        AC_MSG_RESULT(test program got EPERM... assuming yes)
+    elif test $ac_libnet_have_pf_packet = no; then
+        AC_MSG_RESULT(no)
     fi
 
-    if test $ac_libnet_have_pf_packet != choked; then
-        AC_MSG_RESULT($ac_libnet_have_pf_packet)
-    fi
     rm -f pf_packet-test* core core.pf_packet-test
     ;;
     esac])
+
+    if test $ac_libnet_have_pf_packet = yes -o $ac_libnet_have_pf_packet = probably; then
+        AC_DEFINE(HAVE_PF_PACKET)
+    fi
 ])
 
 dnl
@@ -279,6 +262,8 @@ dnl
 
 AC_DEFUN(AC_LIBNET_ENDIAN_CHECK,
     [AC_MSG_CHECKING(machine endianess)
+    AC_CACHE_VAL(ac_cv_libnet_endianess,
+        [
 
     cat > conftest.c << EOF
 #       include <stdio.h>
@@ -332,6 +317,7 @@ dnl failed to compile for some reason
         fi
         rm -f conftest* core core.conftest
 
+        ])
         AC_MSG_RESULT($ac_cv_libnet_endianess)
 
         if test $ac_cv_libnet_endianess = big ; then