diff --git a/configure.in b/configure.in
index 192eafe..14a2d76 100644
--- a/configure.in
+++ b/configure.in
@@ -37,7 +37,7 @@ esac
 AC_DEFINE_UNQUOTED([SYSTEM_HOST], [$ac_system_host], [Set this to your system host (Linux, Solaris, OpenBSD, NetBSD, FreeBSD or Darwin)])
 
 dnl treat Darwin special in Makefiles
-AM_CONDITIONAL(DARWIN, test x$ac_system_host = Darwin)
+AM_CONDITIONAL(DARWIN, test x$ac_system_host = xDarwin)
 
 AC_MSG_CHECKING(whether to enable debugging)
 AC_ARG_ENABLE(debug,