diff --git a/cpdfua.ml b/cpdfua.ml
index 68581ee..b185525 100644
--- a/cpdfua.ml
+++ b/cpdfua.ml
@@ -1494,7 +1494,7 @@ let check_unicode tu n =
 let matterhorn_31_028 _ _ pdf =
   iter
     (fun i ->
-      let tu = (Pdfcmap.parse_tounicode pdf (Pdf.lookup_obj pdf i)).map in
+      let tu = (Pdfcmap.parse_cmap pdf (Pdf.lookup_obj pdf i)).map in
         if check_unicode tu 0 then merror ())
     (all_tounicodes pdf)
 
@@ -1503,7 +1503,7 @@ let matterhorn_31_028 _ _ pdf =
 let matterhorn_31_029 _ _ pdf =
   iter
     (fun i ->
-      let tu = (Pdfcmap.parse_tounicode pdf (Pdf.lookup_obj pdf i)).map in
+      let tu = (Pdfcmap.parse_cmap pdf (Pdf.lookup_obj pdf i)).map in
         if check_unicode tu 0xFEFF || check_unicode tu 0xFFFE then merror ())
     (all_tounicodes pdf)