@search_results = WillPaginate::Collection.create(page, per_page) do |pager|
  xs = ActsAsXapian::Search.new(@search_models, @search_term, {:offset => pager.offset, :limit => pager.per_page})
  results = xs.results.map {|r| r[:model] }
  pager.replace(results)
  pager.total_entries = xs.matches_estimated
end

## alternatively