* lib/rubygems/package/old.rb: Fix loading old format gems on ruby

1.8.  This commit is only so trunk and rubygems master have the same
  code.


git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@39145 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

ChangeLog

@@ -1,3 +1,9 @@
+Fri Feb  8 08:58:26 2013  Eric Hodel  <drbrain@segment7.net>
+
+	* lib/rubygems/package/old.rb:  Fix loading old format gems on ruby
+	  1.8.  This commit is only so trunk and rubygems master have the same
+	  code.
+
 Fri Feb  8 08:53:27 2013  Aaron Patterson <aaron@tenderlovemaking.com>
 
 	* ext/psych/lib/psych/visitors/yaml_tree.rb: fixing string quotation

lib/rubygems/package/old.rb

@@ -142,9 +142,19 @@ class Gem::Package::Old < Gem::Package
       end
     end
 
-    @spec = Gem::Specification.from_yaml yaml
-  rescue YAML::SyntaxError => e
-    raise Gem::Exception, "Failed to parse gem specification out of gem file"
+    yaml_error = if RUBY_VERSION < '1.8' then
+                   YAML::ParseError
+                 elsif YAML::ENGINE.yamler == 'syck' then
+                   YAML::ParseError
+                 else
+                   YAML::SyntaxError
+                 end
+
+    begin
+      @spec = Gem::Specification.from_yaml yaml
+    rescue yaml_error => e
+      raise Gem::Exception, "Failed to parse gem specification out of gem file"
+    end
   rescue ArgumentError => e
     raise Gem::Exception, "Failed to parse gem specification out of gem file"
   end