a bit more language work + changelog changes for pbkdf2hmac
diff --git a/docs/changelog.rst b/docs/changelog.rst
index be42b5d..f401fe7 100644
--- a/docs/changelog.rst
+++ b/docs/changelog.rst
@@ -14,7 +14,7 @@
 * Improved thread-safety for the OpenSSL backend.
 * Fixed compilation on systems where OpenSSL's ``ec.h`` header is not
   available, such as CentOS.
-* Added PBKDF2HMAC support to OpenSSL backend.
+* Added :class:`~cryptography.hazmat.primitives.kdf.pbkdf2.PBKDF2HMAC`.
 
 0.1 - 2014-01-08
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