diff --git a/AUTHORS b/AUTHORS
index c143fe03..fad03b91 100644
--- a/AUTHORS
+++ b/AUTHORS
@@ -1 +1,2 @@
 Bjoern I. Dahlgren <bjodah@gmail.com>
+Sean P. Cornelius <spcornelius@gmail.com>
diff --git a/CHANGES.rst b/CHANGES.rst
index a20fec68..2b6320a2 100644
--- a/CHANGES.rst
+++ b/CHANGES.rst
@@ -1,6 +1,10 @@
+v0.12.3
+=======
+- Support for sparse jacobians. Implementation by @spcornelius
+
 v0.12.2
 =======
-- cvodes code now support multiple precisions (sundials may be compiled with float, double or long double)
+- cvodes code now support multiple precisions (sundials may be compiled with float, double or long double). Implementation by @spcornelius
 
 v0.12.1
 =======
diff --git a/pyodesys/util.py b/pyodesys/util.py
index 86e9a2db..839dea68 100644
--- a/pyodesys/util.py
+++ b/pyodesys/util.py
@@ -5,12 +5,17 @@
 import inspect
 import math
 import operator
+import sys
 
 from pkg_resources import parse_requirements, parse_version
 
 import numpy as np
 import pytest
 
+if sys.version_info < (3, 6, 0):
+    class ModuleNotFoundError(ImportError):
+        pass
+
 
 def stack_1d_on_left(x, y):
     """ Stack a 1D array on the left side of a 2D array