diff --git a/activerecord/lib/active_record/migration.rb b/activerecord/lib/active_record/migration.rb
index ca692c4362..97ac39a350 100644
--- a/activerecord/lib/active_record/migration.rb
+++ b/activerecord/lib/active_record/migration.rb
@@ -457,28 +457,28 @@ module ActiveRecord
 
       destination_migrations = ActiveRecord::Migrator.migrations(destination)
       last = destination_migrations.last
-      sources.each do |name, path|
+      sources.each do |scope, path|
         source_migrations = ActiveRecord::Migrator.migrations(path)
 
         source_migrations.each do |migration|
           source = File.read(migration.filename)
-          source = "# This migration comes from #{name} (originally #{migration.version})\n#{source}"
+          source = "# This migration comes from #{scope} (originally #{migration.version})\n#{source}"
 
           if duplicate = destination_migrations.detect { |m| m.name == migration.name }
-            if options[:on_skip] && !migrations_identical?(File.read(duplicate.filename), source)
-              options[:on_skip].call(name, migration)
+            if options[:on_skip] && duplicate.scope != scope.to_s
+              options[:on_skip].call(scope, migration)
             end
             next
           end
 
           migration.version = next_migration_number(last ? last.version + 1 : 0).to_i
-          new_path = File.join(destination, "#{migration.version}_#{migration.name.underscore}.#{name}.rb")
+          new_path = File.join(destination, "#{migration.version}_#{migration.name.underscore}.#{scope}.rb")
           old_path, migration.filename = migration.filename, new_path
           last = migration
 
           File.open(migration.filename, "w") { |f| f.write source }
           copied << migration
-          options[:on_copy].call(name, migration, old_path) if options[:on_copy]
+          options[:on_copy].call(scope, migration, old_path) if options[:on_copy]
           destination_migrations << migration
         end
       end
@@ -493,22 +493,6 @@ module ActiveRecord
         "%.3d" % number
       end
     end
-
-    def migrations_identical?(a, b)
-      # Due to a bug some of the migrations copied may not have origin comment,
-      # so we need to ignore it.
-      remove_origin_comment(a.chomp) == remove_origin_comment(b.chomp)
-    end
-    private :migrations_identical?
-
-    def remove_origin_comment(migration_source)
-      if migration_source =~ /^# This migration comes from/
-        migration_source = migration_source.lines.to_a[1..-1].join
-      end
-
-      migration_source
-    end
-    private :remove_origin_comment
   end
 
   # MigrationProxy is used to defer loading of the actual migration classes
diff --git a/activerecord/test/cases/migration_test.rb b/activerecord/test/cases/migration_test.rb
index c185efe1d6..b5fae3b7d3 100644
--- a/activerecord/test/cases/migration_test.rb
+++ b/activerecord/test/cases/migration_test.rb
@@ -2226,7 +2226,7 @@ if ActiveRecord::Base.connection.supports_migrations?
       clear
     end
 
-    def test_skip_is_not_called_if_migrations_are_identical
+    def test_skip_is_not_called_if_migrations_are_from_the_same_plugin
       @migrations_path = MIGRATIONS_ROOT + "/valid_with_timestamps"
       @existing_migrations = Dir[@migrations_path + "/*.rb"]
 
@@ -2244,31 +2244,6 @@ if ActiveRecord::Base.connection.supports_migrations?
       clear
     end
 
-    def test_skip_ignores_origin_comment
-      ActiveRecord::Base.timestamped_migrations = false
-      @migrations_path = MIGRATIONS_ROOT + "/valid"
-      @existing_migrations = Dir[@migrations_path + "/*.rb"]
-
-      sources = ActiveSupport::OrderedHash.new
-      sources[:bukkits] = MIGRATIONS_ROOT + "/to_copy"
-
-      skipped = []
-      on_skip = Proc.new { |name, migration| skipped << "#{name} #{migration.name}" }
-      copied = ActiveRecord::Migration.copy(@migrations_path, sources, :on_skip => on_skip)
-
-      # remove origin comment
-      migration = @migrations_path + "/4_people_have_hobbies.bukkits.rb"
-      migration_source = File.read(migration).lines.to_a[1..-1].join
-      File.open(migration, "w") { |f| f.write migration_source }
-
-      ActiveRecord::Migration.copy(@migrations_path, sources, :on_skip => on_skip)
-
-      assert_equal 2, copied.length
-      assert_equal 0, skipped.length
-    ensure
-      clear
-    end
-
     def test_copying_migrations_to_non_existing_directory
       @migrations_path = MIGRATIONS_ROOT + "/non_existing"
       @existing_migrations = []