diff --git a/actionpack/lib/action_view/helpers/asset_tag_helper.rb b/actionpack/lib/action_view/helpers/asset_tag_helper.rb
index 96976ce..039f143 100644
--- a/actionpack/lib/action_view/helpers/asset_tag_helper.rb
+++ b/actionpack/lib/action_view/helpers/asset_tag_helper.rb
@@ -11,7 +11,7 @@ module ActionView
     # the assets exist before linking to them:
     #
     #   image_tag("rails.png")
-    #   # => <img alt="Rails src="/images/rails.png?1230601161" />
+    #   # => <img alt="Rails" src="/images/rails.png?1230601161" />
     #   stylesheet_link_tag("application")
     #   # => <link href="/stylesheets/application.css?1232285206" media="screen" rel="stylesheet" type="text/css" />
     #
@@ -530,7 +530,7 @@ module ActionView
         options.symbolize_keys!
 
         src = options[:src] = path_to_image(source)
-        options[:alt]     ||= File.basename(src, '.*').split('.').first.to_s.capitalize
+        options[:alt]     ||= File.basename(src, '.*').to_s.capitalize
 
         if size = options.delete(:size)
           options[:width], options[:height] = size.split("x") if size =~ %r{^\d+x\d+$}
diff --git a/actionpack/test/template/asset_tag_helper_test.rb b/actionpack/test/template/asset_tag_helper_test.rb
index 586de66..8ca0990 100644
--- a/actionpack/test/template/asset_tag_helper_test.rb
+++ b/actionpack/test/template/asset_tag_helper_test.rb
@@ -141,13 +141,16 @@ class AssetTagHelperTest < ActionView::TestCase
 
   ImageLinkToTag = {
     %(image_tag("xml.png")) => %(<img alt="Xml" src="/images/xml.png" />),
-    %(image_tag("..jpg")) => %(<img alt="" src="/images/..jpg" />),
+    %(image_tag("..jpg")) => %(<img alt="." src="/images/..jpg" />),
     %(image_tag("rss.gif", :alt => "rss syndication")) => %(<img alt="rss syndication" src="/images/rss.gif" />),
     %(image_tag("gold.png", :size => "45x70")) => %(<img alt="Gold" height="70" src="/images/gold.png" width="45" />),
     %(image_tag("gold.png", "size" => "45x70")) => %(<img alt="Gold" height="70" src="/images/gold.png" width="45" />),
     %(image_tag("error.png", "size" => "45")) => %(<img alt="Error" src="/images/error.png" />),
     %(image_tag("error.png", "size" => "45 x 70")) => %(<img alt="Error" src="/images/error.png" />),
     %(image_tag("error.png", "size" => "x")) => %(<img alt="Error" src="/images/error.png" />),
+    %(image_tag("google.com.png")) => %(<img alt="Google.com" src="/images/google.com.png" />),
+    %(image_tag("slash..png")) => %(<img alt="Slash." src="/images/slash..png" />),
+    %(image_tag(".pdf.png")) => %(<img alt=".pdf" src="/images/.pdf.png" />),
     %(image_tag("http://www.rubyonrails.com/images/rails.png")) => %(<img alt="Rails" src="http://www.rubyonrails.com/images/rails.png" />),
     %(image_tag("mouse.png", :mouseover => "/images/mouse_over.png")) => %(<img alt="Mouse" onmouseover="this.src='/images/mouse_over.png'" onmouseout="this.src='/images/mouse.png'" src="/images/mouse.png" />),
     %(image_tag("mouse.png", :mouseover => image_path("mouse_over.png"))) => %(<img alt="Mouse" onmouseover="this.src='/images/mouse_over.png'" onmouseout="this.src='/images/mouse.png'" src="/images/mouse.png" />)