diff --git a/src/intl/gettext/libintl.c b/src/intl/gettext/libintl.c
index 0db88b2dd..85f655be0 100644
--- a/src/intl/gettext/libintl.c
+++ b/src/intl/gettext/libintl.c
@@ -146,7 +146,7 @@ language_to_iso639(int language)
 }
 
 int
-name_to_language(unsigned char *name)
+name_to_language(const unsigned char *name)
 {
 	int i;
 
diff --git a/src/intl/gettext/libintl.h b/src/intl/gettext/libintl.h
index c62b75deb..105ab3fa7 100644
--- a/src/intl/gettext/libintl.h
+++ b/src/intl/gettext/libintl.h
@@ -170,7 +170,7 @@ struct language {
 extern struct language languages[];
 
 /* These two calls return 1 (english) if the code/name wasn't found. */
-extern int name_to_language(unsigned char *name);
+extern int name_to_language(const unsigned char *name);
 extern int iso639_to_language(unsigned char *iso639);
 
 extern unsigned char *language_to_name(int language);