diff --git a/NEWS b/NEWS
index a4d35e30..c1f90275 100644
--- a/NEWS
+++ b/NEWS
@@ -1,5 +1,8 @@
 = RubyMotion 2.25 =
 
+  * Improved use of `WeakRef' to raise an exception when trying to create a
+    weak reference to one of the unsupported classes. For more information, see
+    `Which classes don’t support weak references?' at http://bit.ly/1iiSOaU.
   * Fixed a bug where KVC property validation methods defined in Ruby would not
     be compiled with the appropriate (Pointer) types.
   * Added some introspection support to `ImmediateRef'. It can now report the
diff --git a/test/test/spec/weakref_spec.rb b/test/test/spec/weakref_spec.rb
index 4a72f96a..5b1f104a 100644
--- a/test/test/spec/weakref_spec.rb
+++ b/test/test/spec/weakref_spec.rb
@@ -107,6 +107,11 @@ describe "WeakRef" do
     WeakRef.new(true).should == true
     WeakRef.new(false).should == false
   end
+
+  it "raises with classes that do not support weak references" do
+    obj = NSMutableParagraphStyle.new
+    lambda { WeakRef.new(obj) }.should.raise(WeakRef::RefError)
+  end
 end
 
 describe "Proc#weak!" do
diff --git a/vm b/vm
index b199941d..a8a981d8 160000
--- a/vm
+++ b/vm
@@ -1 +1 @@
-Subproject commit b199941d59a809a3d98fe7130bc2e6aed56c95ce
+Subproject commit a8a981d8f3e479e920a7fb49797d6982994bf06c