diff --git a/src/configure.ac b/src/configure.ac
index 4b2046d..dfbe512 100644
--- a/src/configure.ac
+++ b/src/configure.ac
@@ -2077,7 +2077,7 @@
 	librubyarg=`$vi_cv_path_ruby -r rbconfig -e "print $ruby_rbconfig.expand($ruby_rbconfig::CONFIG[['LIBRUBYARG']])"`
 	librubya=`$vi_cv_path_ruby -r rbconfig -e "print $ruby_rbconfig.expand($ruby_rbconfig::CONFIG[['LIBRUBY_A']])"`
 	rubylibdir=`$vi_cv_path_ruby -r rbconfig -e "print $ruby_rbconfig.expand($ruby_rbconfig::CONFIG[['libdir']])"`
-	if test -f "$rubylibdir/$librubya" || expr "$librubyarg" : "-lruby"; then
+	if test -f "$rubylibdir/$librubya" || expr "$librubyarg" : "-lruby" >/dev/null; then
 	  RUBY_LIBS="$RUBY_LIBS -L$rubylibdir"
 	elif test "$librubyarg" = "libruby.a"; then
 	  dnl required on Mac OS 10.3 where libruby.a doesn't exist