diff --git a/rubygem-native-package-installer.spec b/rubygem-native-package-installer.spec
index c45d894..1d90696 100644
--- a/rubygem-native-package-installer.spec
+++ b/rubygem-native-package-installer.spec
@@ -33,12 +33,11 @@ BuildArch:		noarch
 Documentation for %{name}.
 
 %prep
-gem unpack %{SOURCE0}
-%setup -q -D -T -n  %{gem_name}-%{version}
-gem spec %{SOURCE0} -l --ruby > %{gem_name}.gemspec
+%setup -q -n %{gem_name}-%{version}
+mv ../%{gem_name}-%{version}.gemspec .
 
 %build
-gem build %{gem_name}.gemspec
+gem build ./%{gem_name}-%{version}.gemspec
 %gem_install
 
 %install