diff --git a/nsock/src/configure b/nsock/src/configure
index 0ca555ef7..a86df8b38 100755
--- a/nsock/src/configure
+++ b/nsock/src/configure
@@ -3539,10 +3539,7 @@ fi
 
     ;;
   included)
-    LIBPCAP_INC=${top_nmap_srcdir}/libpcap
-    LIBPCAP_LIB=${top_nmap_srcdir}/libpcap
-    LIBPCAP_LIBS=${LIBPCAP_LIB}/libpcap.a
-    have_libpcap=yes
+    have_libpcap=no
    ;;
   no)
     ;;
@@ -3611,6 +3608,12 @@ fi
 fi
 
 
+if test "$with_libpcap" != "no" -a "$have_libpcap" = "no"; then
+  LIBPCAP_INC=${top_nmap_srcdir}/libpcap
+  LIBPCAP_LIB=${top_nmap_srcdir}/libpcap
+  LIBPCAP_LIBS=${LIBPCAP_LIB}/libpcap.a
+  have_libpcap=yes
+fi
 if test "$have_libpcap" != "no"; then
   $as_echo "#define HAVE_PCAP 1" >>confdefs.h
 
diff --git a/nsock/src/configure.ac b/nsock/src/configure.ac
index f6bf5b696..75f8ee5e3 100644
--- a/nsock/src/configure.ac
+++ b/nsock/src/configure.ac
@@ -128,10 +128,7 @@ AC_HELP_STRING([--without-libpcap], [Disable pcap functions.]),
       have_libpcap=yes ])
     ;;
   included)
-    LIBPCAP_INC=${top_nmap_srcdir}/libpcap
-    LIBPCAP_LIB=${top_nmap_srcdir}/libpcap
-    LIBPCAP_LIBS=${LIBPCAP_LIB}/libpcap.a
-    have_libpcap=yes
+    have_libpcap=no
    ;;
   no)
     ;;
@@ -155,6 +152,12 @@ AC_HELP_STRING([--without-libpcap], [Disable pcap functions.]),
   esac]
 )
 
+if test "$with_libpcap" != "no" -a "$have_libpcap" = "no"; then
+  LIBPCAP_INC=${top_nmap_srcdir}/libpcap
+  LIBPCAP_LIB=${top_nmap_srcdir}/libpcap
+  LIBPCAP_LIBS=${LIBPCAP_LIB}/libpcap.a
+  have_libpcap=yes
+fi
 if test "$have_libpcap" != "no"; then
   AC_DEFINE(HAVE_PCAP)
   if test "${LIBPCAP_INC+set}" = "set"; then