diff --git a/comments/comments.js b/comments/comments.js
index 552efbfd099f19ff2e67096d15a0fa13e37387ea..3081404efe50a00d82bbe236530f2b4f9e90418e 100644
--- a/comments/comments.js
+++ b/comments/comments.js
@@ -207,18 +207,19 @@ Comments.prototype = {
     },
 
     /**
-     * Marks comment as deleted.
+     * Marks comment as deleted or not deleted.
      *
-     * @param {Object} action A delete action:
-     * @param {Number} action.id ID of the comment to delete.
-     * @param {Number} action.user_id ID of the user doing the delete.
+     * @param {Object} action An action config:
+     * @param {Number} action.id ID of the comment.
+     * @param {Number} action.user_id ID of the user doing the delete or undelete.
+     * @param {Boolean} action.deleted True to delete, false to undo delete.
      * @param {Error} callback.err The error object.
      * @param {Function} callback Called when done.
      */
     setDeleted: function(action, callback) {
         var data = {
             id: action.id,
-            deleted: 1
+            deleted: action.deleted ? 1 : 0
         };
         this.db.update("comments", data, function(err) {
             if (err) {
@@ -228,7 +229,7 @@ Comments.prototype = {
             this.db.insert("updates", {
                 comment_id: action.id,
                 user_id: action.user_id,
-                action: 'delete',
+                action: action.deleted ? 'delete' : 'undo_delete',
                 created_at: new Date()
             }, callback);
         }.bind(this));
diff --git a/comments/comments.spec.js b/comments/comments.spec.js
index 7b033fc6c6a036ea2d0eea5c0d8bb893755ab412..f529a975e388429f36ddba84f3510e6c7c89bc6d 100644
--- a/comments/comments.spec.js
+++ b/comments/comments.spec.js
@@ -187,8 +187,8 @@ describe("Comments", function() {
         });
     });
 
-    it("#setDeleted marks comment as deleted, so it can't be accessed any more", function(done) {
-        comments.setDeleted({id: 10, user_id: 1}, function(err) {
+    it("#setDeleted(true) marks comment as deleted, so it can't be accessed any more", function(done) {
+        comments.setDeleted({deleted: true, id: 10, user_id: 1}, function(err) {
             comments.getById(10, function(err, newCom) {
                 expect(newCom).toEqual(null);
                 done();
@@ -196,4 +196,13 @@ describe("Comments", function() {
         });
     });
 
+    it("#setDeleted(false) undoes the delete, so comment can be accessed again", function(done) {
+        comments.setDeleted({deleted: false, id: 10, user_id: 1}, function(err) {
+            comments.getById(10, function(err, newCom) {
+                expect(newCom).not.toEqual(null);
+                done();
+            });
+        });
+    });
+
 });