diff --git a/configure b/configure
index ccdf62e..8da9b5e 100755
--- a/configure
+++ b/configure
@@ -1588,7 +1588,7 @@
   # disables platform specific features beyond repair.
   # On Mac OS X 10.3, defining _POSIX_C_SOURCE or _XOPEN_SOURCE
   # has no effect, don't bother defining them
-  Darwin/[78].*)
+  Darwin/[789].*)
     define_xopen_source=no
     ;;
 
diff --git a/configure.in b/configure.in
index 54cd3c1..542463e 100644
--- a/configure.in
+++ b/configure.in
@@ -236,7 +236,7 @@
   # disables platform specific features beyond repair.
   # On Mac OS X 10.3, defining _POSIX_C_SOURCE or _XOPEN_SOURCE 
   # has no effect, don't bother defining them
-  Darwin/@<:@78@:>@.*)
+  Darwin/@<:@789@:>@.*)
     define_xopen_source=no
     ;;