diff --git a/configure b/configure
index d71501098a9..2c2e81c4a74 100755
--- a/configure
+++ b/configure
@@ -374,7 +374,7 @@ engine_enable() {
 	fi
 	engine=`echo $eng | sed 's/-/_/g'`
 	if test "$opt" = "static" -o "$opt" = "dynamic" -o "$opt" = "yes" ; then
-		if test "`get_engine_build ${engine}`" != "$opt" ; then
+		if test "`get_engine_name ${engine}`" != "" -a "`get_engine_build ${engine}`" != "$opt" ; then
 			eval _engine_${engine}_build=$opt
 		else
 			option_error
@@ -387,7 +387,7 @@ engine_enable() {
 # Disable the given engine
 engine_disable() {
 	engine=`echo $1 | sed 's/-/_/g'`
-	if test "`get_engine_build $engine`" != "no" ; then
+	if test "`get_engine_name ${engine}`" != "" -a "`get_engine_build $engine`" != "no" ; then
 		eval _engine_${engine}_build=no
 	else
 		option_error