diff --git a/lib/hx509/NTMakefile b/lib/hx509/NTMakefile
index 871c4ee5a..ee1bb69d0 100644
--- a/lib/hx509/NTMakefile
+++ b/lib/hx509/NTMakefile
@@ -1,6 +1,6 @@
 ########################################################################
 #
-# Copyright (c) 2009-2016, Secure Endpoints Inc.
+# Copyright (c) 2009-2017, Secure Endpoints Inc.
 # All rights reserved.
 # 
 # Redistribution and use in source and binary forms, with or without
@@ -192,7 +192,7 @@ $(OBJ)\sel-gram.c: sel-gram.y
 	$(YACC) -o $@ --defines=$(OBJ)\sel-gram.h sel-gram.y
 
 $(OBJ)\sel-lex.c: sel-lex.l
-	$(LEX) -o$@ sel-lex.l
+	$(LEX) -P_hx509_sel_yy -o$@ sel-lex.l
 
 all:: $(INCFILES) $(LIBHX509)
 
diff --git a/lib/hx509/sel-gram.y b/lib/hx509/sel-gram.y
index 7f7c9980e..7e9d4f26d 100644
--- a/lib/hx509/sel-gram.y
+++ b/lib/hx509/sel-gram.y
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2008 Kungliga Tekniska Högskolan
+ * Copyright (c) 2017 Kungliga Tekniska Högskolan
  * (Royal Institute of Technology, Stockholm, Sweden).
  * All rights reserved.
  *
@@ -39,6 +39,18 @@
 #include <stdlib.h>
 #include <hx_locl.h>
 
+#if !defined(yylex)
+#define yylex   _hx509_sel_yylex
+#define yywrap  _hx509_sel_yywrap
+#endif
+#if !defined(yyparse)
+#define yyparse _hx509_sel_yyparse
+#define yyerror _hx509_sel_yyerror
+#define yylval  _hx509_sel_yylval
+#define yychar  _hx509_sel_yychar
+#define yydebug _hx509_sel_yydebug
+#define yynerrs _hx509_sel_yynerrs
+#endif
 
 %}
 
diff --git a/lib/hx509/sel-lex.l b/lib/hx509/sel-lex.l
index 92911b0c9..f401e40e3 100644
--- a/lib/hx509/sel-lex.l
+++ b/lib/hx509/sel-lex.l
@@ -1,6 +1,6 @@
 %{
 /*
- * Copyright (c) 2004, 2008 Kungliga Tekniska Högskolan
+ * Copyright (c) 2004 - 2017 Kungliga Tekniska Högskolan
  * (Royal Institute of Technology, Stockholm, Sweden).
  * All rights reserved.
  *
@@ -120,6 +120,10 @@ handle_string(void)
     return strdup(x);
 }
 
+#if !defined(yywrap)
+#define yywrap  _hx509_sel_yywrap
+#endif
+
 int
 yywrap ()
 {