diff --git a/Manifest.txt b/Manifest.txt
index 8419de28..3b398674 100644
--- a/Manifest.txt
+++ b/Manifest.txt
@@ -79,6 +79,7 @@ spec/public/associations/many_to_one_spec.rb
 spec/public/associations/many_to_one_with_boolean_cpk_spec.rb
 spec/public/associations/one_to_many_spec.rb
 spec/public/associations/one_to_one_spec.rb
+spec/public/associations/one_to_one_with_boolean_cpk_spec.rb
 spec/public/collection_spec.rb
 spec/public/migrations_spec.rb
 spec/public/model/relationship_spec.rb
diff --git a/lib/dm-core/associations/many_to_one.rb b/lib/dm-core/associations/many_to_one.rb
index 1d89630d..9768cc0b 100644
--- a/lib/dm-core/associations/many_to_one.rb
+++ b/lib/dm-core/associations/many_to_one.rb
@@ -145,7 +145,7 @@ def initialize(name, source_model, target_model, options = {})
         #
         # @api private
         def lazy_load(source)
-          return unless source_key.get(source).all?
+          return unless source_key.get(source).all? { |value| !value.nil? }
 
           # SEL: load all related resources in the source collection
           if source.saved? && source.collection.size > 1
diff --git a/lib/dm-core/associations/one_to_one.rb b/lib/dm-core/associations/one_to_one.rb
index 05f1f6b3..2fbf8d2f 100644
--- a/lib/dm-core/associations/one_to_one.rb
+++ b/lib/dm-core/associations/one_to_one.rb
@@ -15,7 +15,7 @@ class Relationship < Associations::Relationship
         def get(source, other_query = nil)
           assert_kind_of 'source', source, source_model
 
-          return unless loaded?(source) || source_key.get(source).all?
+          return unless loaded?(source) || source_key.get(source).all? { |value| !value.nil? }
 
           relationship.get(source, other_query).first
         end
diff --git a/lib/dm-core/resource.rb b/lib/dm-core/resource.rb
index 21d7cb33..d1a4b605 100644
--- a/lib/dm-core/resource.rb
+++ b/lib/dm-core/resource.rb
@@ -90,7 +90,7 @@ def key
         original_attributes[property] || (property.loaded?(self) ? property.get!(self) : nil)
       end
 
-      return unless key.all?
+      return unless key.all? { |value| !value.nil? }
 
       # memoize the key if the Resource is not frozen
       @key = key unless frozen?
diff --git a/spec/public/associations/one_to_one_with_boolean_cpk_spec.rb b/spec/public/associations/one_to_one_with_boolean_cpk_spec.rb
new file mode 100644
index 00000000..11f192b1
--- /dev/null
+++ b/spec/public/associations/one_to_one_with_boolean_cpk_spec.rb
@@ -0,0 +1,45 @@
+require File.expand_path(File.join(File.dirname(__FILE__), '..', '..', 'spec_helper'))
+
+# TODO: combine this into one_to_one_spec.rb
+
+describe 'One to One Associations when foreign key is part of a composite key and contains a boolean, with an integer and a boolean making up the composite key' do
+  before :all do
+    class ::ParentModel
+      include DataMapper::Resource
+
+      property :integer_key, Integer, :key => true
+      property :boolean_key, Boolean, :key => true
+
+      has 1, :child_model, :child_key => [ :integer_key, :boolean_key ]
+    end
+
+    class ::ChildModel
+      include DataMapper::Resource
+
+      property :integer_key,       Integer, :key => true
+      property :other_integer_key, Integer, :key => true
+      property :boolean_key,       Boolean, :key => true
+
+      belongs_to :parent_model, :child_key => [ :integer_key, :boolean_key ]
+    end
+  end
+
+  supported_by :all do
+    before :all do
+      @parent = ParentModel.create(:integer_key => 1, :boolean_key => false)
+      @child  = ChildModel.create(:integer_key => 1, :other_integer_key => 1, :boolean_key => false)
+    end
+
+    it 'should be able to access the child' do
+      @parent.child_model.should == @child
+    end
+
+    it 'should be able to access the parent' do
+      @child.parent_model.should == @parent
+    end
+
+    it 'should be able to access the parent_key' do
+      @child.parent_model.key.should_not be_nil
+    end
+  end
+end