--- pari-2.5.4.ebuild	2013-05-16 14:18:42.148137162 +1200
+++ pari-2.5.4-r1.ebuild	2013-06-05 21:55:13.452932596 +1200
@@ -74,6 +74,7 @@
 
 src_configure() {
 	tc-export CC
+	export CPLUSPLUS=$(tc-getCXX)
 
 	# need to force optimization here, as it breaks without
 	if is-flag -O0; then
@@ -102,13 +103,17 @@
 		mymake=DLLD\="${EPREFIX}"/usr/bin/gcc\ DLLDFLAGS\=-shared\ -Wl,-soname=\$\(LIBPARI_SONAME\)\ -lm
 	fi
 
+	if use qt4; then
+		mycxxmake=LD\=$(tc-getCXX)
+	fi
+
 	local installdir=$(get_compile_dir)
 	cd "${installdir}" || die "failed to change directory"
 	# upstream set -fno-strict-aliasing.
 	# aliasing is a known issue on amd64, work on x86 by sheer luck
 	emake ${mymake} \
 		CFLAGS="${CFLAGS} -fno-strict-aliasing -DGCC_INLINE -fPIC" lib-dyn
-	emake ${mymake} \
+	emake ${mymake} ${mycxxmake} \
 		CFLAGS="${CFLAGS} -DGCC_INLINE" gp ../gp
 
 	if use doc; then