--- a/mcabber/mcabber/utils.h	Mon Oct 12 11:41:34 2015 +0200
+++ b/mcabber/mcabber/utils.h	Mon Oct 12 17:19:19 2015 +0200
@@ -21,8 +21,8 @@
                   const char *resource);
 gboolean jid_equal(const char *jid1, const char *jid2);
 
-void fingerprint_to_hex(const char *fpr, char hex[48]);
-gboolean hex_to_fingerprint(const char *hex, char fpr[17]);
+void fingerprint_to_hex(const char *fpr,     char *hex, size_t fpr_len);
+gboolean hex_to_fingerprint(const char *hex, char *fpr, size_t fpr_len);
 
 void ut_init_debug(void);
 void ut_write_log(unsigned int flag, const char *data);