Use tilt to support other templating languages, like haml.

README.rdoc

@@ -18,7 +18,7 @@ And, of course, install the gem:
 
 Done! From now on users with IE version lower than 7.0 will get a nice error message saying that their browsers need to be updated... Ok, ok, not so nice message, you can personalize it by putting an <tt>upgrade.html</tt> file inside the <tt>/public</tt> directory of your application.
 
-<em>- Cool!, what about something more dynamic... like ERB?</em>
+<em>- Cool!, what about something more dynamic... like ERB or HAML?</em>
 
 Granted! You'll have to add to the config which template to use. In <tt>environment.rb</tt>:
 

Rakefile

@@ -23,6 +23,7 @@ begin
     gemspec.summary = "Rack Middleware for filtering by user agent"
     gemspec.add_dependency('rack', '>= 0.9.1')
     gemspec.add_dependency('useragent', '>=0.1.4')
+    gemspec.add_dependency('tilt', '>=1.0.0')
   end
 rescue LoadError
 end

lib/rack/user_agent/filter.rb

@@ -1,5 +1,6 @@
 require 'user_agent'
 require 'erb'
+require 'tilt'
 require 'ostruct'
 
 module Rack::UserAgent
@@ -35,7 +36,7 @@ def detection_disabled_by_cookie?(cookies)
     def render_page(browser)
       if @template && File.exists?(@template)
         @browser = browser # for the template
-        ERB.new(File.read(@template)).result(binding)
+        Tilt.new(@template).render(self)
       else
         "Sorry, your browser is not supported. Please upgrade" 
       end

test/fixtures/upgrade.haml

@@ -0,0 +1 @@
+= "Hello, #{@browser.browser} #{@browser.version}!"

test/user_agent_filter_test.rb

@@ -54,6 +54,24 @@ def app
 
   end
 
+  context "custom page (haml)" do
+    setup do
+      def app
+        Rack::Builder.new do
+           use Rack::UserAgent::Filter, [{:browser => "Internet Explorer", :version => "7.0"}], :template => File.dirname(__FILE__) + "/fixtures/upgrade.haml"
+           run SampleApp.new
+         end
+      end
+    end
+
+    should "work" do
+      header "User-Agent", @outdated_browser
+      get '/'
+      assert_equal "Hello, Internet Explorer 6.0!\n", last_response.body
+    end
+
+  end
+
   context "cookie" do
 
     setup do