diff --git a/CHANGELOG.md b/CHANGELOG.md
index 684096bb44b397bb6c5b43ea9b966545b39304d3..beb020fd007033de4716377d42f24deb5c64fd4c 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,5 +1,12 @@
 ## Release notes
-# 6.0.5 (in preparation)
+# 6.0.6 (in preparation)
+
+### Features:
+ - Add external ode-solver interface with [Sundials CVODE
+   library](http://computation.llnl.gov/projects/sundials-suite-nonlinear-differential-algebraic-equation-solvers/cvode).
+
+## Release notes
+# 6.0.5
 
 ### Features:
  - Added an ODE solver library that can solve transient and nonlinear processes