diff --git a/m4/virt-yajl.m4 b/m4/virt-yajl.m4
index adf2819eeb..8c452adca6 100644
--- a/m4/virt-yajl.m4
+++ b/m4/virt-yajl.m4
@@ -26,7 +26,7 @@ AC_DEFUN([LIBVIRT_CHECK_YAJL],[
     AC_PATH_PROGS([QEMU], [qemu-kvm qemu kvm qemu-system-x86_64],
                   [], [$PATH:/usr/bin:/usr/libexec])
     if test -x "$QEMU"; then
-      if `$QEMU -help | grep libvirt` >/dev/null; then
+      if $QEMU -help 2>/dev/null | grep -q libvirt; then
         with_yajl=yes
       else
         [qemu_version_sed='s/.*ersion \([0-9.,]*\).*/\1/']