"defaultValue: true" evaluates to false

I’m using:

DEBUG: ------------------------------- 
DEBUG: Ember      : 1.3.1
DEBUG: Ember Data : 1.0.0-beta.6
DEBUG: Handlebars : 1.3.0 
DEBUG: jQuery     : 2.0.2 
DEBUG: ------------------------------- 

I have the following Ember Data model:

App.User = DS.Model.extend({
  name: DS.attr("string"),
  thisShouldBeFalse: DS.attr("boolean", {defaultValue: false}),
  thisShouldBeTrue: DS.attr("boolean", {defaultValue: true})

When manually creating a model instance, and leaving thisShouldBeTrue unspecified, then thisShouldBeTrue has the value true. This is expected.

model = this.store.createRecord("user", {
  id: "12356",
  name: "Foo Bar"
model.get("thisShouldBeTrue") //evaluates to true. This is expected

When instead querying the store/RESTAdapter for a model instance, and the remote server’s REST API endpoint leaves thisShouldBeTrue unspecified, then thisShouldBeTrue has the value false. This is unexpected.

model = this.store.find("user", "12356");
//an XHR to the API endpoint takes place... then later...
model.get("thisShouldBeTrue"); //evaluates to false. This is unexpected

Is this a bug in Ember Data’s defaultValue logic in conjunction with RESTAdapter?

P.S.: I’d like to provide a JSFiddle/JS Bin example that utilizes RESTAdapter, but I couldn’t find a public JSON API endpoint that follows Ember Data’s naming conventions out-of-the-box.