diff --git a/Library/Homebrew/formulary.rb b/Library/Homebrew/formulary.rb
index 74b506d7d5..3815105c27 100644
--- a/Library/Homebrew/formulary.rb
+++ b/Library/Homebrew/formulary.rb
@@ -2,22 +2,43 @@
 # It is not meant to be used directy from formulae.
 
 class Formulary
+  module Formulae
+    class << self
+      if instance_method(:const_defined?).arity == -1
+        def formula_const_defined?(name)
+          const_defined?(name, false)
+        end
+
+        def formula_const_get(name)
+          const_get(name, false)
+        end
+      else
+        def formula_const_defined?(name)
+          const_defined?(name)
+        end
+
+        def formula_const_get(name)
+          const_get(name)
+        end
+      end
+
+      def remove_formula_const(name)
+        remove_const(name)
+      end
+
+      def formula_const_set(name, value)
+        const_set(name, value)
+      end
+    end
+  end
 
   def self.unload_formula formula_name
-    Object.send(:remove_const, class_s(formula_name))
-  end
-
-  def self.formula_class_defined? class_name
-    Object.const_defined?(class_name)
-  end
-
-  def self.get_formula_class class_name
-    Object.const_get(class_name)
+    Formulae.remove_formula_const(class_s(formula_name))
   end
 
   def self.restore_formula formula_name, value
     old_verbose, $VERBOSE = $VERBOSE, nil
-    Object.const_set(class_s(formula_name), value)
+    Formulae.formula_const_set(class_s(formula_name), value)
   ensure
     $VERBOSE = old_verbose
   end
@@ -50,11 +71,9 @@ class Formulary
       klass.new(name, path, spec)
     end
 
-    # Return the Class for this formula, `require`-ing it if
-    # it has not been parsed before.
     def klass
       begin
-        have_klass = Formulary.formula_class_defined? class_name
+        have_klass = Formulae.formula_const_defined?(class_name)
       rescue NameError => e
         raise unless e.name.to_s == class_name
         raise FormulaUnavailableError, name, e.backtrace
@@ -62,11 +81,7 @@ class Formulary
 
       load_file unless have_klass
 
-      klass = Formulary.get_formula_class(class_name)
-      if klass == Formula || !(klass < Formula)
-        raise FormulaUnavailableError.new(name)
-      end
-      klass
+      Formulae.formula_const_get(class_name)
     end
 
     private
@@ -74,7 +89,7 @@ class Formulary
     def load_file
       STDERR.puts "#{$0} (#{self.class.name}): loading #{path}" if ARGV.debug?
       raise FormulaUnavailableError.new(name) unless path.file?
-      require(path)
+      Formulae.module_eval(path.read, path)
     end
   end