diff --git a/sysutils/contool/patches/patch-lex_c b/sysutils/contool/patches/patch-lex_c
new file mode 100644
index 00000000000..92c17988bad
--- /dev/null
+++ b/sysutils/contool/patches/patch-lex_c
@@ -0,0 +1,13 @@
+$OpenBSD: patch-lex_c,v 1.1 2002/12/11 23:31:20 pvalchev Exp $
+--- lex.c.orig	Wed Dec 11 13:30:45 2002
++++ lex.c	Wed Dec 11 13:31:11 2002
+@@ -126,7 +126,8 @@ char	*s;
+ /************************************************************************/
+ PRIVATE	int	yylex()
+ 
+-{	register	char	c, c1, *p;
++{	register	signed char c, c1;
++	register	char *p;
+ 	register	int	i, j, val;
+ 	double			atof();
+ 
diff --git a/sysutils/contool/patches/patch-parse_y b/sysutils/contool/patches/patch-parse_y
new file mode 100644
index 00000000000..c21b7729612
--- /dev/null
+++ b/sysutils/contool/patches/patch-parse_y
@@ -0,0 +1,12 @@
+$OpenBSD: patch-parse_y,v 1.1 2002/12/11 23:31:20 pvalchev Exp $
+--- parse.y.orig	Wed Dec 11 13:27:40 2002
++++ parse.y	Wed Dec 11 13:27:51 2002
+@@ -37,7 +37,7 @@ PRIVATE	char	*get_last_token();
+ PRIVATE	Filter	*curr;
+ PRIVATE	char	*curr_file;
+ PRIVATE	int	line_count = 1;
+-PRIVATE	char	lastc = -1;
++PRIVATE	signed char lastc = -1;
+ 
+ %}
+