diff --git a/src/terminal/draw.c b/src/terminal/draw.c
index 76cd7377..53a5e45d 100644
--- a/src/terminal/draw.c
+++ b/src/terminal/draw.c
@@ -357,10 +357,17 @@ draw_char(struct terminal *term, int x, int y,
 	set_screen_dirty(term->screen, y, y);
 }
 
+#ifdef CONFIG_UTF8
+void
+draw_box(struct terminal *term, struct el_box *box,
+	 unicode_val_T data, int attr,
+	 struct color_pair *color)
+#else
 void
 draw_box(struct terminal *term, struct el_box *box,
 	 unsigned char data, int attr,
 	 struct color_pair *color)
+#endif /* CONFIG_UTF8 */
 {
 	struct screen_char *line, *pos, *end;
 	int width, height;
diff --git a/src/terminal/draw.h b/src/terminal/draw.h
index abb3d06b..3f6e93ab 100644
--- a/src/terminal/draw.h
+++ b/src/terminal/draw.h
@@ -270,9 +270,15 @@ void draw_char(struct terminal *term, int x, int y,
 #endif /* CONFIG_UTF8 */
 
 /** Draws area defined by @a box using the same colors and attributes. */
+#ifdef CONFIG_UTF8
+void draw_box(struct terminal *term, struct el_box *box,
+	      unicode_val_T data, int attr,
+	      struct color_pair *color);
+#else
 void draw_box(struct terminal *term, struct el_box *box,
 	      unsigned char data, int attr,
 	      struct color_pair *color);
+#endif
 
 /** Draws a shadow of @a width and @a height with color @a color
  * around @a box. */