diff --git a/configure.in b/configure.in
index cbda0ce02..b59fe8c3b 100644
--- a/configure.in
+++ b/configure.in
@@ -312,6 +312,11 @@ fi ;;
 
 esac
 
+dnl Define variables for YACC and LEX
+AC_PROG_YACC
+AM_PROG_LEX
+
+
 dnl Check for a few typdefs:
 AC_TYPE_PID_T
 AC_TYPE_SIGNAL
@@ -540,12 +545,11 @@ fi
 AC_SUBST(EKVDIR)
 AC_SUBST(EKVLIB)
 
+
 dnl Add new code models to the build by pointing to them here.
 if test "$enable_xspice" = "yes"; then
     AC_MSG_RESULT(X-Spice features included)
     AC_DEFINE(XSPICE,[],[The xspice enhancements])
-    AC_PROG_YACC
-    AM_PROG_LEX
     XSPICEDIR="xspice"
     case $host_os in
      *mingw* | *cygwin* )
diff --git a/src/xspice/cmpp/Makefile.am b/src/xspice/cmpp/Makefile.am
index 15b857a83..10a9af8c8 100644
--- a/src/xspice/cmpp/Makefile.am
+++ b/src/xspice/cmpp/Makefile.am
@@ -6,8 +6,7 @@ EXTRA_DIST = ifs_lex.l mod_lex.l ifs_yacc.h mod_yacc.h
 
 MAINTAINERCLEANFILES = Makefile.in
 
-AM_YFLAGS = -d
-
+YACC = @YACC@ -d
 LEX = @LEX@ -t
 
 bin_PROGRAMS = cmpp