diff --git a/activerecord/lib/active_record/connection_adapters/postgresql_adapter.rb b/activerecord/lib/active_record/connection_adapters/postgresql_adapter.rb
index 913bb52..77c4083 100644
--- a/activerecord/lib/active_record/connection_adapters/postgresql_adapter.rb
+++ b/activerecord/lib/active_record/connection_adapters/postgresql_adapter.rb
@@ -865,8 +865,7 @@ module ActiveRecord
 
         # Construct a clean list of column names from the ORDER BY clause, removing
         # any ASC/DESC modifiers
-        order_columns = order_by.split(',').collect { |s| s.split.first }
-        order_columns.delete_if &:blank?
+        order_columns = parse_order_by(order_by).collect(&:first)
         order_columns = order_columns.zip((0...order_columns.size).to_a).map { |s,i| "#{s} AS alias_#{i}" }
 
         # Return a DISTINCT ON() clause that's distinct on the columns we want but includes
@@ -881,11 +880,10 @@ module ActiveRecord
       # by wrapping the +sql+ string as a sub-select and ordering in that query.
       def add_order_by_for_association_limiting!(sql, options) #:nodoc:
         return sql if options[:order].blank?
-        
-        order = options[:order].split(',').collect { |s| s.strip }.reject(&:blank?)
-        order.map! { |s| 'DESC' if s =~ /\bdesc$/i }
+
+        order = parse_order_by(options[:order]).collect(&:last)
         order = order.zip((0...order.size).to_a).map { |s,i| "id_list.alias_#{i} #{s}" }.join(', ')
-        
+
         sql.replace "SELECT * FROM (#{sql}) AS id_list ORDER BY #{order}"
       end
 
@@ -1045,6 +1043,40 @@ module ActiveRecord
              ORDER BY a.attnum
           end_sql
         end
+
+        def parse_order_by(order_by)
+          order_columns = []
+          apos = false
+          quot = false
+          paren = 0
+          brack = 0
+          acc = ""
+          (order_by.split(//)+[',']).each do |c|
+            acc << c
+            case c
+            when '('
+              paren += 1 unless apos or quot
+            when ')'
+              paren -= 1 unless apos or quot
+            when '['
+              brack += 1 unless apos or quot
+            when ']'
+              brack -= 1 unless apos or quot
+            when '"'
+              quot = !quot unless apos
+            when "'"
+              apos = !apos unless quot
+            when ','
+              unless apos or quot or paren > 0 or brack > 0
+                match = /^(.*?)((\s+(ASC|DESC))?(\s+NULLS\s+(FIRST|LAST))?)\s*,$/i.match(acc)
+                # [ordering expression, modifier flags]
+                order_columns << [match[1].strip, match[2].strip.upcase]
+                acc = ''
+              end
+            end
+          end
+          order_columns.delete_if(&:blank?)
+        end
     end
   end
 end
diff --git a/activerecord/test/cases/associations/eager_test.rb b/activerecord/test/cases/associations/eager_test.rb
index 4072381..4fa36f4 100644
--- a/activerecord/test/cases/associations/eager_test.rb
+++ b/activerecord/test/cases/associations/eager_test.rb
@@ -500,6 +500,30 @@ class EagerAssociationTest < ActiveRecord::TestCase
     assert_equal posts_with_explicit_order, posts_with_scoped_order
   end
 
+  if current_adapter?(:PostgreSQLAdapter)
+    def test_eager_with_scoped_order_using_association_limiting_without_explicit_scope_with_nulls_first_and_last
+      posts_with_explicit_order = Post.find(:all, :conditions => 'comments.id is not null', :include => :comments, :order => 'posts.id DESC NULLS FIRST', :limit => 2)
+      posts_with_scoped_order = Post.with_scope(:find => {:order => 'posts.id DESC NULLS FIRST'}) do
+        Post.find(:all, :conditions => 'comments.id is not null', :include => :comments, :limit => 2)
+      end
+      assert_equal posts_with_explicit_order, posts_with_scoped_order
+
+      posts_with_explicit_order = Post.find(:all, :conditions => 'comments.id is not null', :include => :comments, :order => 'posts.id DESC NULLS LAST', :limit => 2)
+      posts_with_scoped_order = Post.with_scope(:find => {:order => 'posts.id DESC NULLS LAST'}) do
+        Post.find(:all, :conditions => 'comments.id is not null', :include => :comments, :limit => 2)
+      end
+      assert_equal posts_with_explicit_order, posts_with_scoped_order
+    end
+
+    def test_eager_with_scoped_order_using_association_limiting_without_explicit_scope_order_with_function
+      posts_with_explicit_order = Post.find(:all, :include => :comments, :order => 'coalesce(comments.id, 0) DESC', :limit => 2)
+      posts_with_scoped_order = Post.with_scope(:find => {:order => 'coalesce(comments.id, 0) DESC'}) do
+        Post.find(:all, :include => :comments, :limit => 2)
+      end
+      assert_equal posts_with_explicit_order, posts_with_scoped_order
+    end
+  end
+
   def test_eager_association_loading_with_habtm
     posts = Post.find(:all, :include => :categories, :order => "posts.id")
     assert_equal 2, posts[0].categories.size