diff -urN ppp-2.4.3.orig/pppd/Makefile.linux ppp-2.4.3/pppd/Makefile.linux
--- ppp-2.4.3.orig/pppd/Makefile.linux	2006-02-05 20:13:06.000000000 +0100
+++ ppp-2.4.3/pppd/Makefile.linux	2006-02-05 20:24:22.000000000 +0100
@@ -172,8 +172,8 @@
 
 ifdef FILTER
 ifneq ($(wildcard /usr/include/pcap-bpf.h),)
-LIBS    += -lpcap
-CFLAGS  += -DPPP_FILTER
+LIBS    += -lpcap -L$(STAGING_DIR)/usr/lib
+CFLAGS  += -DPPP_FILTER -I$(STAGING_DIR)/usr/include
 endif
 endif