diff --git a/fftw.spec b/fftw.spec
index 622a700..444c954 100644
--- a/fftw.spec
+++ b/fftw.spec
@@ -1,6 +1,6 @@
 Name:           fftw
 Version:        3.3
-Release:        1%{?dist}
+Release:        2%{?dist}
 Summary:        A Fast Fourier Transform library
 Group:          System Environment/Libraries
 License:        GPLv2+
@@ -8,7 +8,22 @@ URL:            http://www.fftw.org
 Source0:        http://www.fftw.org/fftw-%{version}.tar.gz
 BuildRoot:      %{_tmppath}/%{name}-%{version}-%{release}-root-%(%{__id_u} -n)
 
+# OpenMP support not available on RHEL 4
+%if 0%{?rhel} == 4
+BuildRequires:  gcc-g77
+%global openmp 0
+%else
 BuildRequires:  gcc-gfortran
+%global openmp 1
+%endif
+
+# Quad precision support only available with gcc >= 4.6
+%if 0%{?fedora} >= 15
+%global quad 1
+%else
+%global quad 0
+%endif
+
 # For check phase
 BuildRequires:  time
 BuildRequires:  perl
@@ -39,9 +54,10 @@ Group:          Development/Libraries
 Requires:       pkgconfig
 Requires:       %{name}%{?_isa} = %{version}-%{release}
 Requires:       %{name}-libs%{?_isa} = %{version}-%{release}
-Requires:       %{name}-libs-openmp%{?_isa} = %{version}-%{release}
 Requires:       %{name}-libs-threads%{?_isa} = %{version}-%{release}
-
+%if %{openmp}
+Requires:       %{name}-libs-openmp%{?_isa} = %{version}-%{release}
+%endif
 Provides:       fftw3-devel%{?_isa} = %{version}-%{release}
 Obsoletes:      fftw3-devel%{?_isa} < 3.3
 
@@ -60,12 +76,14 @@ Group:          Development/Libraries
 %description libs-threads
 This package contains the FFTW library compiled with threading support.
 
+%if %{openmp}
 %package libs-openmp
 Summary:        FFTW library with OpenMP support
 Group:          Development/Libraries
 
 %description libs-openmp
 This package contains the FFTW library compiled with OpenMP support.
+%endif
 
 %package        static
 Summary:        Static versions of the FFTW libraries
@@ -81,7 +99,9 @@ the FFTW fast Fourier transform library.
 %package doc
 Summary:        FFTW library manual
 Group:          Documentation
+%if 0%{?rhel} > 5 || 0%{?fedora} > 12
 BuildArch:      noarch
+%endif
 
 %description doc
 This package contains the manual for the FFTW fast Fourier transform
@@ -91,9 +111,18 @@ library.
 %setup -q
 
 %build
+%if 0%{?rhel} == 4
+# System fortran compiler is g77
+export F77=g77
+%else
 # Configure uses g77 by default, if present on system
 export F77=gfortran
-BASEFLAGS="--enable-shared --disable-dependency-tracking --enable-threads --enable-openmp"
+%endif
+
+BASEFLAGS="--enable-shared --disable-dependency-tracking --enable-threads"
+%if %{openmp}
+BASEFLAGS="$BASEFLAGS --enable-openmp"
+%endif
 
 # Precisions to build
 prec_name[0]=single
@@ -108,7 +137,12 @@ prec_flags[2]=--enable-long-double
 prec_flags[3]=--enable-quad-precision
 
 # Loop over precisions
-for((iprec=0;iprec<4;iprec++)); do
+%if %{quad}
+for((iprec=0;iprec<4;iprec++))
+%else
+for((iprec=0;iprec<3;iprec++))
+%endif
+do
  mkdir ${prec_name[iprec]}${ver_name[iver]}
  cd ${prec_name[iprec]}${ver_name[iver]}
  ln -s ../configure .
@@ -121,7 +155,12 @@ done
 
 %install
 rm -rf %{buildroot}
-for ver in single double long quad; do
+%if %{quad}
+for ver in single double long quad
+%else
+for ver in single double long
+%endif
+do
  make -C $ver install DESTDIR=%{buildroot}
 done
 rm -f %{buildroot}%{_infodir}/dir
@@ -129,7 +168,12 @@ rm -f %{buildroot}%{_libdir}/*.la
 
 %check
 bdir=`pwd`
-for ver in single double long quad; do
+%if %{quad}
+for ver in single double long quad
+%else
+for ver in single double long
+%endif
+do 
  export LD_LIBRARY_PATH=$bdir/$ver/.libs:$bdir/$ver/threads/.libs
  make -C $ver check
 done
@@ -139,10 +183,12 @@ rm -rf %{buildroot}
 
 %post libs -p /sbin/ldconfig
 %postun libs -p /sbin/ldconfig
-%post libs-openmp -p /sbin/ldconfig
-%postun libs-openmp -p /sbin/ldconfig
 %post libs-threads -p /sbin/ldconfig
 %postun libs-threads -p /sbin/ldconfig
+%if %{openmp}
+%post libs-openmp -p /sbin/ldconfig
+%postun libs-openmp -p /sbin/ldconfig
+%endif
 
 %post devel
 /sbin/install-info --section="Math" %{_infodir}/%{name}.info.gz %{_infodir}/dir  2>/dev/null || :
@@ -163,21 +209,29 @@ fi
 %{_libdir}/libfftw3.so.*
 %{_libdir}/libfftw3f.so.*
 %{_libdir}/libfftw3l.so.*
+%if %{quad}
 %{_libdir}/libfftw3q.so.*
+%endif
 
+%if %{openmp}
 %files libs-openmp
 %defattr(-,root,root,-)
 %{_libdir}/libfftw3_omp.so.*
 %{_libdir}/libfftw3f_omp.so.*
 %{_libdir}/libfftw3l_omp.so.*
+%if %{quad}
 %{_libdir}/libfftw3q_omp.so.*
+%endif
+%endif
 
 %files libs-threads
 %defattr(-,root,root,-)
 %{_libdir}/libfftw3_threads.so.*
 %{_libdir}/libfftw3f_threads.so.*
 %{_libdir}/libfftw3l_threads.so.*
+%if %{quad}
 %{_libdir}/libfftw3q_threads.so.*
+%endif
 
 %files devel
 %defattr(-,root,root,-)
@@ -196,6 +250,10 @@ fi
 %{_libdir}/libfftw3*.a
 
 %changelog
+* Sat Jul 30 2011 Jussi Lehtola <jussilehtola@fedoraproject.org> - 3.3-2
+- Conditionalize OpenMP and quadruple precision support based on capabilities
+  of system compiler.
+
 * Thu Jul 28 2011 Jussi Lehtola <jussilehtola@fedoraproject.org> - 3.3-1
 - Update to 3.3.