diff --git a/xep.ent b/xep.ent
index d147491b..3f08d469 100644
--- a/xep.ent
+++ b/xep.ent
@@ -483,6 +483,7 @@ THE SOFTWARE.
 <!ENTITY rfc3342 "<span class='ref'><link url='http://tools.ietf.org/html/rfc3342'>RFC 3342</link></span> <note>RFC 3342: The Application Exchange (APEX) Option Party Pack, Part Deux! &lt;<link url='http://tools.ietf.org/html/rfc3342'>http://tools.ietf.org/html/rfc3342</link>&gt;.</note>" >
 <!ENTITY rfc3343 "<span class='ref'><link url='http://tools.ietf.org/html/rfc3343'>RFC 3343</link></span> <note>RFC 3343: The Application Exchange (APEX) Presence Service &lt;<link url='http://tools.ietf.org/html/rfc3343'>http://tools.ietf.org/html/rfc3343</link>&gt;.</note>" >
 <!ENTITY rfc3370 "<span class='ref'><link url='http://tools.ietf.org/html/rfc3370'>RFC 3370</link></span> <note>RFC 3370: Cryptographic Message Syntax (CMS) Algorithms &lt;<link url='http://tools.ietf.org/html/rfc3370'>http://tools.ietf.org/html/rfc3370</link>&gt;.</note>" >
+<!ENTITY rfc3389 "<span class='ref'><link url='http://tools.ietf.org/html/rfc3389'>RFC 3389</link></span> <note>RFC 3389: Real-time Transport Protocol (RTP) Payload for Comfort Noise (CN) &lt;<link url='http://tools.ietf.org/html/rfc3389'>http://tools.ietf.org/html/rfc3389</link>&gt;.</note>" >
 <!ENTITY rfc3394 "<span class='ref'><link url='http://tools.ietf.org/html/rfc3394'>RFC 3394</link></span> <note>RFC 3394: Advanced Encryption Standard (AES) Key Wrap Algorithm &lt;<link url='http://tools.ietf.org/html/rfc3394'>http://tools.ietf.org/html/rfc3394</link>&gt;.</note>" >
 <!ENTITY rfc3401 "<span class='ref'><link url='http://tools.ietf.org/html/rfc3401'>RFC 3401</link></span> <note>RFC 3401: Dynamic Delegation Discovery System (DDDS) Part One: The Comprehensive DDDS &lt;<link url='http://tools.ietf.org/html/rfc3401'>http://tools.ietf.org/html/rfc3401</link>&gt;.</note>" >
 <!ENTITY rfc3403 "<span class='ref'><link url='http://tools.ietf.org/html/rfc3403'>RFC 3403</link></span> <note>RFC 3403: Dynamic Delegation Discovery System (DDDS) Part Three: The Domain Name System (DNS) Database &lt;<link url='http://tools.ietf.org/html/rfc3403'>http://tools.ietf.org/html/rfc3403</link>&gt;.</note>" >