--- sigscheme/configure.orig	2007-09-25 00:33:59.000000000 +0900
+++ sigscheme/configure	2007-09-25 00:34:05.000000000 +0900
@@ -44974,7 +44974,9 @@
   _ax_feature_list_expanded=''
   for feature in $ax_feature_list_all; do
     _ax_feature_val=`eval echo '${'use_$feature'}'`
-    _ax_feature_val=${_ax_feature_val:no}
+    if test -z $_ax_feature_val; then
+      _ax_feature_val=no
+    fi
     if test "x$_ax_feature_val" != xno; then
       _ax_feature_list_expanded="$_ax_feature_list_expanded $feature"
     fi