diff --git a/perl-Crypt-DSA.spec b/perl-Crypt-DSA.spec
index 9ad88e2..7036774 100644
--- a/perl-Crypt-DSA.spec
+++ b/perl-Crypt-DSA.spec
@@ -6,7 +6,6 @@ License:	GPL+ or Artistic
 Group:		Development/Libraries
 Url:		http://search.cpan.org/dist/Crypt-DSA/
 Source0:	http://search.cpan.org/CPAN/authors/id/A/AD/ADAMK/Crypt-DSA-%{version}.tar.gz
-BuildRoot:	%{_tmppath}/%{name}-%{version}-%{release}-root-%(id -nu)
 Requires:	perl(:MODULE_COMPAT_%(eval "`perl -V:version`"; echo $version))
 BuildArch:	noarch
 BuildRequires:	perl(Convert::PEM)
@@ -18,6 +17,7 @@ BuildRequires:	perl(File::Spec)
 BuildRequires:	perl(File::Which) >= 0.05
 BuildRequires:	perl(IPC::Open3)
 BuildRequires:	perl(Math::BigInt) >= 1.78
+BuildRequires:	perl(Math::BigInt::GMP)
 BuildRequires:	perl(Perl::MinimumVersion) >= 1.20
 BuildRequires:	perl(Test::CPAN::Meta) >= 0.12
 BuildRequires:	perl(Test::More) >= 0.42
@@ -26,16 +26,8 @@ BuildRequires:	perl(Test::Pod) >= 1.26
 BuildRequires:	openssl
 # Crypt::DSA::Keychain calls openssl for DSA parameter generation
 Requires:	openssl
-
-# Pull in Math::BigInt::GMP for GMP support for suitably recent versions of Math::BigInt
-# else use Math::GMP
-%if %(perl -MMath::BigInt -e 'use Math::BigInt 1.87;' 2>/dev/null && echo 1 || echo 0)
-BuildRequires:	perl(Math::BigInt::GMP)
+# Some operations are really slow without GMP (or Pari, but we test with GMP)
 Requires:	perl(Math::BigInt::GMP)
-%else
-BuildRequires:	perl(Math::GMP)
-Requires:	perl(Math::GMP)
-%endif
 
 %description
 Crypt::DSA is an implementation of the DSA (Digital Signature Algorithm)
@@ -50,8 +42,7 @@ perl Makefile.PL INSTALLDIRS=vendor
 make %{?_smp_mflags}
 
 %install
-rm -rf %{buildroot}
-make pure_install PERL_INSTALL_ROOT=%{buildroot}
+make pure_install DESTDIR=%{buildroot}
 find %{buildroot} -type f -name .packlist -exec rm -f {} ';'
 find %{buildroot} -depth -type d -exec rmdir {} ';' 2>/dev/null
 chmod -R u+w %{buildroot}
@@ -60,11 +51,7 @@ chmod -R u+w %{buildroot}
 make test
 make test AUTOMATED_TESTING=1 TEST_FILES="xt/*.t"
 
-%clean
-rm -rf %{buildroot}
-
 %files
-%defattr(-,root,root,-)
 %doc Changes LICENSE README
 %{perl_vendorlib}/Crypt/
 %{_mandir}/man3/Crypt::DSA.3pm*
@@ -85,6 +72,7 @@ rm -rf %{buildroot}
 - Drop upstreamed patches
 - Release tests moved to xt/ directory upstream and now tested separately
 - Nobody else likes macros for commands
+- Drop backwards compatibility with ancient distributions
 
 * Tue Feb 08 2011 Fedora Release Engineering <rel-eng@lists.fedoraproject.org> - 1.16-6
 - Rebuilt for https://fedoraproject.org/wiki/Fedora_15_Mass_Rebuild