diff --git a/library/ssl_srv.c b/library/ssl_srv.c
index a19179a..b1da073 100644
--- a/library/ssl_srv.c
+++ b/library/ssl_srv.c
@@ -4361,7 +4361,10 @@
     }
 
     /* Calculate hash and verify signature */
-    ssl->handshake->calc_verify( ssl, hash );
+    {
+        size_t dummy_hlen;
+        ssl->handshake->calc_verify( ssl, hash, &dummy_hlen );
+    }
 
     if( ( ret = mbedtls_pk_verify( peer_pk,
                            md_alg, hash_start, hashlen,