diff --git a/Library/Homebrew/extend/pathname.rb b/Library/Homebrew/extend/pathname.rb
index 8a940af0a7..0a4264c7e5 100644
--- a/Library/Homebrew/extend/pathname.rb
+++ b/Library/Homebrew/extend/pathname.rb
@@ -134,8 +134,8 @@ class Pathname
     /-((\d+\.)*\d+([abc]|rc|RC)\d*)$/.match stem
     return $1 if $1
 
-    # eg foobar-4.5.0-beta1
-    /-((\d+\.)*\d+-beta\d+)$/.match stem
+    # eg foobar-4.5.0-beta1, or foobar-4.50-beta
+    /-((\d+\.)*\d+-beta(\d+)?)$/.match stem
     return $1 if $1
 
     # eg. foobar4.5.1
diff --git a/Library/Homebrew/test/test_versions.rb b/Library/Homebrew/test/test_versions.rb
index c726d2596c..8010cf1c5d 100644
--- a/Library/Homebrew/test/test_versions.rb
+++ b/Library/Homebrew/test/test_versions.rb
@@ -65,6 +65,10 @@ class VersionTests < Test::Unit::TestCase
     check "http://camaya.net/download/gloox-1.0-beta7.tar.bz2", '1.0-beta7'
   end
 
+  def test_sphinx_beta_style
+    check 'http://sphinxsearch.com/downloads/sphinx-1.10-beta.tar.gz', '1.10-beta'
+  end
+
   def test_astyle_verson_style
     check "http://kent.dl.sourceforge.net/sourceforge/astyle/astyle_1.23_macosx.tar.gz",
       '1.23'