magnet.go | 2 +-

diff --git a/magnet.go b/magnet.go
index 7b274ceb43a44af13a442c1287115f0cd4d08e0d..848e3de39068fe278e1a4d326ddb57a32fe57173 100644
--- a/magnet.go
+++ b/magnet.go
@@ -43,7 +43,7 @@ 			return nil
 		}
 	}()
 	if decode == nil {
-		err = fmt.Errorf("unhandled xt parameter encoding")
+		err = fmt.Errorf("unhandled xt parameter encoding: encoded length %d", len(xt))
 		return
 	}
 	n, err := decode(m.InfoHash[:], []byte(xt))