diff --git a/libpcap/Makefile.in b/libpcap/Makefile.in
index e71d973ca..04c4608a0 100644
--- a/libpcap/Makefile.in
+++ b/libpcap/Makefile.in
@@ -69,9 +69,6 @@ INSTALL_PROGRAM = @INSTALL_PROGRAM@
 INSTALL_DATA = @INSTALL_DATA@
 RANLIB = @RANLIB@
 
-LEX = @LEX@
-YACC = @YACC@
-
 # Explicitly define compilation rule since SunOS 4's make doesn't like gcc.
 # Also, gcc does not remove the .o before forking 'as', which can be a
 # problem if you don't own the file but can write to the directory.
@@ -156,7 +153,7 @@ TAGFILES = \
 	$(SRC) $(HDR)
 
 CLEANFILES = $(OBJ) libpcap.* $(TESTS) \
-	$(PROG)-`cat $(srcdir)/VERSION`.tar.gz $(GENSRC) $(GENHDR) \
+	$(PROG)-`cat $(srcdir)/VERSION`.tar.gz \
 	lex.yy.c pcap-config
 
 MAN1 = pcap-config.1
@@ -360,6 +357,15 @@ EXTRA_DIST = \
 
 all: libpcap.a shared pcap-config
 
+# Inhibit implicit rule Make seems to have for using yacc/lex to
+# recompile new scanner.c/grammar.c -- we ship ones which we want to
+# use instead.
+grammar.c:
+	echo "Not rebuilding grammar.c"
+
+scanner.c:
+	echo "Not rebuilding scanner.c"
+
 libpcap.a: $(OBJ)
 	@rm -f $@
 	$(AR) rc $@ $(OBJ) $(ADDLARCHIVEOBJS)
@@ -443,22 +449,11 @@ libpcap.shareda: $(OBJ)
 #
 libpcap.none:
 
-scanner.c: $(srcdir)/scanner.l
-	$(LEX) -P pcap_ --header-file=scanner.h --nounput -o scanner.c $<
-scanner.h: scanner.c
-## Recover from the removal of $@
-	@if test -f $@; then :; else \
-		rm -f scanner.c; \
-		$(MAKE) $(MAKEFLAGS) scanner.c; \
-	fi
-
 scanner.o: scanner.c grammar.h
 	$(CC) $(FULL_CFLAGS) -c scanner.c
 
 pcap.o: pcap_version.h
 
-grammar.c: $(srcdir)/grammar.y
-	$(YACC) -p pcap_ -o grammar.c -d $<
 grammar.h: grammar.c
 ## Recover from the removal of $@
 	@if test -f $@; then :; else \
diff --git a/libpcap/configure.ac b/libpcap/configure.ac
index da2f940da..430086628 100644
--- a/libpcap/configure.ac
+++ b/libpcap/configure.ac
@@ -1140,49 +1140,6 @@ if test "$want_turbocap" != no; then
 	fi
 fi
 
-#
-# Look for {f}lex.
-#
-AC_PROG_LEX
-if test "$LEX" = ":"; then
-	AC_MSG_ERROR([Neither flex nor lex was found.])
-fi
-
-#
-# Make sure {f}lex supports the -P, --header-file, and --nounput flags
-# and supports processing our scanner.l.
-#
-AC_CACHE_CHECK([for capable lex], tcpdump_cv_capable_lex,
-	if $LEX -P pcap_ --header-file=/dev/null --nounput -t $srcdir/scanner.l > /dev/null 2>&1; then
-	    tcpdump_cv_capable_lex=yes
-	else
-	    tcpdump_cv_capable_lex=insufficient
-	fi)
-if test $tcpdump_cv_capable_lex = insufficient ; then
-	AC_MSG_ERROR([$LEX is insufficient to compile libpcap.
- libpcap requires Flex 2.5.31 or later, or a compatible version of lex.])
-fi
-
-#
-# Look for yacc/bison/byacc.
-#
-AC_PROG_YACC
-
-#
-# Make sure it supports the -p flag and supports processing our
-# grammar.y.
-#
-AC_CACHE_CHECK([for capable yacc/bison], tcpdump_cv_capable_yacc,
-	if $YACC -p pcap_ -o /dev/null $srcdir/grammar.y >/dev/null 2>&1; then
-	    tcpdump_cv_capable_yacc=yes
-	else
-	    tcpdump_cv_capable_yacc=insufficient
-	fi)
-if test $tcpdump_cv_capable_yacc = insufficient ; then
-	AC_MSG_ERROR([$YACC is insufficient to compile libpcap.
- libpcap requires Bison, Berkeley YACC, or another YACC compatible with them.])
-fi
-
 #
 # Assume, by default, no support for shared libraries and V7/BSD convention
 # for man pages (file formats in section 5, miscellaneous info in section 7).
@@ -1459,13 +1416,11 @@ AC_SUBST(V_CCOPT)
 AC_SUBST(V_DEFS)
 AC_SUBST(V_FINDALLDEVS)
 AC_SUBST(V_INCLS)
-AC_SUBST(V_LEX)
 AC_SUBST(V_PCAP)
 AC_SUBST(V_SHLIB_CMD)
 AC_SUBST(V_SHLIB_OPT)
 AC_SUBST(V_SONAME_OPT)
 AC_SUBST(V_RPATH_OPT)
-AC_SUBST(V_YACC)
 AC_SUBST(ADDLOBJS)
 AC_SUBST(ADDLARCHIVEOBJS)
 AC_SUBST(SSRC)