diff --git a/rubygem-pango.spec b/rubygem-pango.spec
index 0549f24..5222229 100644
--- a/rubygem-pango.spec
+++ b/rubygem-pango.spec
@@ -75,12 +75,11 @@ Header files and libraries for building a extension library for the
 rubygem-%{gem_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 .
 
 # Allow ruby-gnome2 no less than ones
-sed -i -e 's|= 3\.4\.9|>= 3.4.9|' %{gem_name}.gemspec
+sed -i -e 's|= 3\.4\.9|>= 3.4.9|' %{gem_name}-%{version}.gemspec
 
 # Fix wrong shebang
 
@@ -89,7 +88,7 @@ sed -i -e 's|= 3\.4\.9|>= 3.4.9|' %{gem_name}.gemspec
 %build
 export CONFIGURE_ARGS="--with-cflags='%{optflags}'"
 export CONFIGURE_ARGS="$CONFIGURE_ARGS --with-pkg-config-dir=$(pwd)%{_libdir}/pkgconfig"
-gem build %{gem_name}.gemspec
+gem build %{gem_name}-%{version}.gemspec
 %gem_install