diff --git a/ChangeLog b/ChangeLog
index b0eb36c..22c0ea1 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,6 +1,11 @@
 
 Codecrypt ChangeLog
 
+1.6.1
+
+- simplify padding for symmetric encryption
+- fix possible known-plaintext attack against symmetric encryption padding
+
 1.6
 
 - fix fmtseq short message padding bug (fixed by previous)
diff --git a/configure.ac b/configure.ac
index 956301e..3d88782 100644
--- a/configure.ac
+++ b/configure.ac
@@ -1,6 +1,6 @@
 
 AC_PREREQ(2.6)
-AC_INIT([codecrypt], [1.6])
+AC_INIT([codecrypt], [1.6.1])
 AC_CONFIG_AUX_DIR(.) # because of libtoolize
 AC_CONFIG_MACRO_DIR([m4])