diff --git a/users.js b/users.js
index e4f3996cb3..eabe9c4e80 100644
--- a/users.js
+++ b/users.js
@@ -1142,9 +1142,16 @@ var User = (function () {
 		}
 	};
 	User.prototype.updateChallenges = function() {
+		var challengeTo = this.challengeTo;
+		if (challengeTo) {
+			challengeTo = {
+				to: challengeTo.to,
+				format: challengeTo.format
+			}
+		}
 		this.send('|updatechallenges|'+JSON.stringify({
-			challengesFrom: this.challengesFrom,
-			challengeTo: this.challengeTo
+			challengesFrom: Object.map(this.challengesFrom, 'format'),
+			challengeTo: challengeTo
 		}));
 	};
 	User.prototype.makeChallenge = function(user, format/*, isPrivate*/) {