diff --git a/Rakefile b/Rakefile
index e0e91bd..4ed5c36 100644
--- a/Rakefile
+++ b/Rakefile
@@ -2,10 +2,17 @@ require 'rake'
 require 'rake/testtask'
 require 'rake/rdoctask'
 
+def reset_invoked
+  ['test_rails','test'].each do |name|
+    Rake::Task[name].instance_variable_set '@already_invoked', false
+  end
+end
+
+
 desc 'Default: run unit tests.'
 task :default => :test
 
-desc 'Test the grouped_scope plugin.'
+desc 'Test the GroupedScope plugin.'
 Rake::TestTask.new(:test) do |t|
   t.libs << 'lib'
   t.libs << 'test'
@@ -13,7 +20,18 @@ Rake::TestTask.new(:test) do |t|
   t.verbose = true
 end
 
-desc 'Generate documentation for the grouped_scope plugin.'
+desc 'Test the GroupedScope plugin with Rails 2.1.1, 2.0.4 & 1.2.6 gems'
+task :test_rails do
+  test = Rake::Task['test']
+  versions = ['2.1.1','2.0.4','1.2.6']
+  versions.each do |version|
+    ENV['RAILS_VERSION'] = "#{version}"
+    test.invoke
+    reset_invoked unless version == versions.last
+  end
+end
+
+desc 'Generate documentation for the GroupedScope plugin.'
 Rake::RDocTask.new(:rdoc) do |rdoc|
   rdoc.rdoc_dir = 'rdoc'
   rdoc.title    = 'GroupedScope'
@@ -21,3 +39,5 @@ Rake::RDocTask.new(:rdoc) do |rdoc|
   rdoc.rdoc_files.include('README')
   rdoc.rdoc_files.include('lib/**/*.rb')
 end
+
+
diff --git a/lib/grouped_scope.rb b/lib/grouped_scope.rb
index ec70452..6215d70 100644
--- a/lib/grouped_scope.rb
+++ b/lib/grouped_scope.rb
@@ -5,10 +5,11 @@
 require 'grouped_scope/class_methods'
 require 'grouped_scope/has_many_association'
 require 'grouped_scope/has_many_through_association'
+require 'grouped_scope/core_ext'
 
 module GroupedScope
   
-  VERSION = '0.2'
+  VERSION = '0.3'
     
 end
 
diff --git a/lib/grouped_scope/core_ext.rb b/lib/grouped_scope/core_ext.rb
new file mode 100644
index 0000000..061a7fe
--- /dev/null
+++ b/lib/grouped_scope/core_ext.rb
@@ -0,0 +1,21 @@
+
+class ActiveRecord::Base
+  
+  class << self
+    
+    private
+    
+    def attribute_condition_with_grouped_scope(argument)
+      case argument
+        when GroupedScope::SelfGroupping then "IN (?)"
+        else attribute_condition_without_grouped_scope(argument)
+      end
+    end
+    
+    alias_method_chain :attribute_condition, :grouped_scope
+    
+  end
+  
+end
+
+
diff --git a/test/grouped_scope/self_grouping_test.rb b/test/grouped_scope/self_grouping_test.rb
index 924988a..9ff7d15 100644
--- a/test/grouped_scope/self_grouping_test.rb
+++ b/test/grouped_scope/self_grouping_test.rb
@@ -33,6 +33,12 @@ def setup
       assert_raise(GroupedScope::NoGroupIdError) { GroupedScope::SelfGroupping.new(FooBar.new) }
     end
     
+    should 'return correct attribute_condition for GroupedScope::SelfGroupping object' do
+      assert_sql(/"?group_id"? IN \(#{@employee.id}\)/) do
+        Employee.find :all, :conditions => {:group_id => @employee.group}
+      end
+    end
+    
     context 'for Array delegates' do
 
       should 'respond to first/last' do
diff --git a/test/lib/boot.rb b/test/lib/boot.rb
index d01aba0..198f292 100644
--- a/test/lib/boot.rb
+++ b/test/lib/boot.rb
@@ -33,6 +33,6 @@
   require 'core_ext'
   require 'named_scope'
   require ActiveRecord::Base.respond_to?(:find_first) ? 'named_scope_patch_1.2.6' : 'named_scope_patch_2.0'
-  ActiveRecord::Base.send :include, GroupedScope::NamedScope
+  ActiveRecord::Base.send :include, ActiveRecord::NamedScope
 end
 
diff --git a/test/lib/named_scope.rb b/test/lib/named_scope.rb
index ccb3460..b30ef97 100644
--- a/test/lib/named_scope.rb
+++ b/test/lib/named_scope.rb
@@ -1,4 +1,4 @@
-module GroupedScope
+module ActiveRecord
   module NamedScope
     # All subclasses of ActiveRecord::Base have two named_scopes:
     # * <tt>all</tt>, which is similar to a <tt>find(:all)</tt> query, and
diff --git a/test/lib/named_scope_patch_1.2.6.rb b/test/lib/named_scope_patch_1.2.6.rb
index 7f2a84a..a63e2b8 100644
--- a/test/lib/named_scope_patch_1.2.6.rb
+++ b/test/lib/named_scope_patch_1.2.6.rb
@@ -6,6 +6,19 @@ def with_scope(*args, &block)
   end
 end
 
+class ActiveRecord::Base
+  class << self
+    private
+    def attribute_condition_with_named_scope(argument)
+      case argument
+        when ActiveRecord::Associations::AssociationCollection, ActiveRecord::NamedScope::Scope then "IN (?)"
+        else attribute_condition_without_named_scope(argument)
+      end
+    end
+    alias_method_chain :attribute_condition, :named_scope
+  end
+end
+
 ActiveRecord::Associations::HasManyAssociation.class_eval do
   protected
   def method_missing(method, *args, &block)
diff --git a/test/lib/named_scope_patch_2.0.rb b/test/lib/named_scope_patch_2.0.rb
index 9a6250b..0751b94 100644
--- a/test/lib/named_scope_patch_2.0.rb
+++ b/test/lib/named_scope_patch_2.0.rb
@@ -6,6 +6,18 @@ def with_scope(*args, &block)
   end
 end
 
+class ActiveRecord::Base
+  class << self
+    private
+    def attribute_condition_with_named_scope(argument)
+      case argument
+        when ActiveRecord::NamedScope::Scope then "IN (?)"
+        else attribute_condition_without_named_scope(argument)
+      end
+    end
+    alias_method_chain :attribute_condition, :named_scope
+  end
+end
 
 ActiveRecord::Associations::AssociationCollection.class_eval do
   protected