Automatically generated revert isn't correct for index

On the latest 3.1.0.rc1 branch, I used the line in a migration:

  def change
    add_index :some_table, [:column1, :column2], :unique => true, :name => "some_table_unique_entries"
  end

The new automatically generated rollback action attempted to revert this change with:

  remove_index :some_table, [:column1, :column2]

which failed because the generated index name from this did not match the overridden index name.