diff -ur ppp-2.4.2.org/pppd/demand.c ppp-2.4.2/pppd/demand.c
--- ppp-2.4.2.org/pppd/demand.c	2004-08-25 00:48:45.280320718 +0200
+++ ppp-2.4.2/pppd/demand.c	2004-08-25 00:36:48.441279079 +0200
@@ -50,8 +50,9 @@
 #include <sys/socket.h>
 #ifdef PPP_FILTER
 #include <net/if.h>
-#include <net/bpf.h>
+#include <pcap-bpf.h>
 #include <pcap.h>
+#include <linux/if_ether.h>
 #endif
 
 #include "pppd.h"
diff -ur ppp-2.4.2.org/pppd/options.c ppp-2.4.2/pppd/options.c
--- ppp-2.4.2.org/pppd/options.c	2004-08-25 00:49:30.960260765 +0200
+++ ppp-2.4.2/pppd/options.c	2004-08-25 01:22:21.523384931 +0200
@@ -56,7 +56,6 @@
 #endif
 #ifdef PPP_FILTER
 #include <pcap.h>
-#include <pcap-int.h>	/* XXX: To get struct pcap */
 #endif
 
 #include "pppd.h"
@@ -122,7 +121,6 @@
 #ifdef PPP_FILTER
 struct	bpf_program pass_filter;/* Filter program for packets to pass */
 struct	bpf_program active_filter; /* Filter program for link-active pkts */
-pcap_t  pc;			/* Fake struct pcap so we can compile expr */
 #endif
 
 char *current_option;		/* the name of the option being parsed */
@@ -1439,12 +1437,24 @@
 setpassfilter(argv)
     char **argv;
 {
-    pc.linktype = DLT_PPP;
-    pc.snapshot = PPP_HDRLEN;
- 
-    if (pcap_compile(&pc, &pass_filter, *argv, 1, netmask) == 0)
+#ifdef DLT_PPP_WITHDIRECTION
+    pcap_t* pc = pcap_open_dead (DLT_PPP_WITHDIRECTION, PPP_HDRLEN);
+#else
+    #warning with libpcap 0.8... you are not able to use IN/OUT filters with DLT_PPP
+    pcap_t* pc = pcap_open_dead (DLT_PPP, PPP_HDRLEN);
+#endif
+    if (!pc) {
+	option_error("error in pass-filter expression: pcap_open_dead failed\n");
+	return 0;
+    }
+
+    if (pcap_compile(pc, &pass_filter, *argv, 1, netmask) == 0) {
+	pcap_close (pc);
 	return 1;
-    option_error("error in pass-filter expression: %s\n", pcap_geterr(&pc));
+    }
+
+    option_error("error in pass-filter expression: %s\n", pcap_geterr(pc));
+    pcap_close (pc);
     return 0;
 }
 
@@ -1455,12 +1465,25 @@
 setactivefilter(argv)
     char **argv;
 {
-    pc.linktype = DLT_PPP;
-    pc.snapshot = PPP_HDRLEN;
- 
-    if (pcap_compile(&pc, &active_filter, *argv, 1, netmask) == 0)
+#ifdef DLT_PPP_WITHDIRECTION
+    pcap_t* pc = pcap_open_dead (DLT_PPP_WITHDIRECTION, PPP_HDRLEN);
+#else
+#warning with libpcap 0.8... you are not able to use IN/OUT filters with DLT_PPP
+    pcap_t* pc = pcap_open_dead (DLT_PPP, PPP_HDRLEN);
+#endif
+
+    if (!pc) {
+	option_error("error in active-filter expression: pcap_open_dead failed\n");
+	return 0;
+    }
+
+    if (pcap_compile(pc, &active_filter, *argv, 1, netmask) == 0) {
+	pcap_close (pc);
 	return 1;
-    option_error("error in active-filter expression: %s\n", pcap_geterr(&pc));
+    }
+
+    option_error("error in active-filter expression: %s\n", pcap_geterr(pc));
+    pcap_close (pc);
     return 0;
 }
 #endif
diff -ur ppp-2.4.2.org/pppd/sys-linux.c ppp-2.4.2/pppd/sys-linux.c
--- ppp-2.4.2.org/pppd/sys-linux.c	2004-08-25 00:49:30.976258643 +0200
+++ ppp-2.4.2/pppd/sys-linux.c	2004-08-25 00:51:26.735901663 +0200
@@ -141,7 +141,7 @@
 #endif /* IPX_CHANGE */
 
 #ifdef PPP_FILTER
-#include <net/bpf.h>
+#include <pcap-bpf.h>
 #include <linux/filter.h>
 #endif /* PPP_FILTER */

diff -ur ppp-2.4.2.org/pppd/demand.c ppp-2.4.2/pppd/demand.c
--- ppp-2.4.2.org/pppd/demand.c	2004-09-21 15:12:36.419304045 +0200
+++ ppp-2.4.2/pppd/demand.c	2004-09-21 15:12:36.419304045 +0200
@@ -349,12 +349,14 @@
 	return 0;
     proto = PPP_PROTOCOL(p);
 #ifdef PPP_FILTER
+    *p = 1; /* set outbound for the filter rule */
     if (pass_filter.bf_len != 0
 	&& bpf_filter(pass_filter.bf_insns, p, len, len) == 0)
 	return 0;
     if (active_filter.bf_len != 0
 	&& bpf_filter(active_filter.bf_insns, p, len, len) == 0)
 	return 0;
+    *p = 0xff; /* restore original ppp header */
 #endif
     for (i = 0; (protp = protocols[i]) != NULL; ++i) {
 	if (protp->protocol < 0xC000 && (protp->protocol & ~0x8000) == proto) {