diff --git a/rubygem-i18n.spec b/rubygem-i18n.spec
index 09dfc69..56f54a7 100644
--- a/rubygem-i18n.spec
+++ b/rubygem-i18n.spec
@@ -4,7 +4,7 @@ Summary: New wave Internationalization support for Ruby
 Name: rubygem-%{gem_name}
 Version: 1.0.0
 Release: 1%{?dist}
-Group: Development/Languages
+# `BSD or Ruby` due to header of lib/i18n/gettext/po_parser.rb
 License: MIT and (BSD or Ruby)
 URL: http://github.com/svenfuchs/i18n
 Source0: https://rubygems.org/gems/%{gem_name}-%{version}.gem
@@ -23,20 +23,16 @@ Ruby Internationalization and localization solution.
 
 %package doc
 Summary: Documentation for %{name}
-Group: Documentation
 Requires:%{name} = %{version}-%{release}
 
 %description doc
 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 -c -T
+%gem_install -n %{SOURCE0}
 
 %build
-gem build %{gem_name}.gemspec
-%gem_install
 
 %install
 mkdir -p %{buildroot}%{gem_dir}
@@ -57,14 +53,14 @@ popd
 %files
 %dir %{gem_instdir}
 %{gem_libdir}
-%doc %{gem_instdir}/README.md
-%doc %{gem_instdir}/MIT-LICENSE
-%{gem_cache}
+%license %{gem_instdir}/MIT-LICENSE
+%exclude %{gem_cache}
 %{gem_spec}
 
 %files doc
 %{gem_instdir}/test
 %{gem_instdir}/gemfiles
+%doc %{gem_instdir}/README.md
 %doc %{gem_docdir}