diff --git a/lib/get-credentials-by-uri.js b/lib/get-credentials-by-uri.js
index 474f615..6fb8f31 100644
--- a/lib/get-credentials-by-uri.js
+++ b/lib/get-credentials-by-uri.js
@@ -19,6 +19,8 @@ function getCredentialsByURI (uri) {
 
   // Handle the old-style _auth=<base64> style for the default
   // registry, if set.
+  //
+  // XXX(isaacs): Remove when npm 1.4 is no longer relevant
   var authDef = this.get("_auth")
   var userDef = this.get("username")
   var passDef = this.get("_password")