diff -ur squid-2.4.DEVEL4.orig/configure.in squid-2.4.DEVEL4/configure.in
--- squid-2.4.DEVEL4.orig/configure.in	Tue Jul 18 02:16:19 2000
+++ squid-2.4.DEVEL4/configure.in	Thu Nov 23 14:54:14 2000
@@ -584,6 +584,17 @@
   fi
 ])
 
+dnl Enable Linux Netfilter (2.4) Transparent Proxy
+AC_ARG_ENABLE(linux-netfilter,
+[  --enable-linux-netfilter
+                          Enable Transparent Proxy support for Linux 2.4.],
+[ if test "$enableval" = "yes" ; then
+	echo "Linux-Netfilter Transparent Proxy enabled"
+	AC_DEFINE(LINUX_NETFILTER)
+	LINUX_NETFILTER="yes"
+  fi
+])
+
 dnl Enable Leak Finding Functions
 AC_ARG_ENABLE(leakfinder,
 [  --enable-leakfinder
@@ -798,6 +809,7 @@
 	ip_nat.h \
 	libc.h \
 	limits.h \
+	linux/netfilter_ipv4.h \
 	malloc.h \
 	math.h \
 	memory.h \
@@ -1255,6 +1267,26 @@
 if test "$IPF_TRANSPARENT" = "no" ; then
     echo "WARNING: Cannot find necessary IP-Filter header files"
     echo "         Transparent Proxy support WILL NOT be enabled"
+    sleep 10
+fi
+
+dnl Linux-Netfilter support requires Linux 2.4 kernel header files.
+dnl Shamelessly copied from above
+if test "$LINUX_NETFILTER" ; then
+    AC_MSG_CHECKING(if Linux 2.4 kernel header files are installed)
+    # hold on to your hats...
+    if test "$ac_cv_header_linux_netfilter_ipv4_h" = "yes"; then
+        LINUX_NETFILTER="yes"
+        AC_DEFINE(LINUX_NETFILTER, 1)
+    else
+        LINUX_NETFILTER="no"
+        AC_DEFINE(LINUX_NETFILTER, 0)
+    fi
+    AC_MSG_RESULT($LINUX_NETFILTER)
+fi 
+if test "$LINUX_NETFILTER" = "no" ; then
+    echo "WARNING: Cannot find necessary Linux 2.4 kernel header files"
+    echo "         Linux 2.4 Transparent Proxy support WILL NOT be enabled"
     sleep 10
 fi
 
diff -ur squid-2.4.DEVEL4.orig/include/autoconf.h.in squid-2.4.DEVEL4/include/autoconf.h.in
--- squid-2.4.DEVEL4.orig/include/autoconf.h.in	Tue Jul 18 02:16:39 2000
+++ squid-2.4.DEVEL4/include/autoconf.h.in	Thu Nov 23 14:54:14 2000
@@ -229,6 +229,11 @@
 #undef IPF_TRANSPARENT
 
 /*
+ * Enable support for Transparent Proxy on Linux 2.4 systems 
+ */
+#undef LINUX_NETFILTER
+
+/*
  * Enable code for assiting in finding memory leaks.  Hacker stuff only.
  */
 #undef USE_LEAKFINDER
diff -ur squid-2.4.DEVEL4.orig/src/client_side.c squid-2.4.DEVEL4/src/client_side.c
--- squid-2.4.DEVEL4.orig/src/client_side.c	Tue Jul 18 02:16:41 2000
+++ squid-2.4.DEVEL4/src/client_side.c	Thu Nov 23 14:54:53 2000
@@ -62,6 +62,9 @@
 #endif
 #endif
 
+#if LINUX_NETFILTER
+#include <linux/netfilter_ipv4.h>
+#endif
 
 
 #if LINGERING_CLOSE
@@ -2227,6 +2230,9 @@
     struct natlookup natLookup;
     static int natfd = -1;
 #endif
+#if LINUX_NETFILTER
+    size_t sock_sz = sizeof(conn->me);
+#endif
 
     if ((req_sz = headersEnd(conn->in.buf, conn->in.offset)) == 0) {
 	debug(33, 5) ("Incomplete request, waiting for end of headers\n");
@@ -2402,6 +2408,10 @@
 		    inet_ntoa(natLookup.nl_realip),
 		    vport, url);
 #else
+#if LINUX_NETFILTER
+	  /* If the call fails the address structure will be unchanged */
+	  getsockopt(conn->fd, SOL_IP, SO_ORIGINAL_DST, &conn->me, &sock_sz );
+#endif
 	    snprintf(http->uri, url_sz, "http://%s:%d%s",
 		inet_ntoa(http->conn->me.sin_addr),
 		vport, url);