diff --git a/configure.in b/configure.in
index f71c4747..fabb6d39 100644
--- a/configure.in
+++ b/configure.in
@@ -1456,8 +1456,6 @@ fi
 AC_DEFINE_UNQUOTED(DBUS_SESSION_SOCKET_DIR, "$DBUS_SESSION_SOCKET_DIR", [Where per-session bus puts its sockets])
 AC_SUBST(DBUS_SESSION_SOCKET_DIR)
 
-AC_DEFINE_UNQUOTED(DBUS_UNIX, "1", [Defined on UNIX and Linux systems and not on Windows])
-
 # darwin needs this to initialize the environment
 AC_CHECK_HEADERS(crt_externs.h)
 AC_CHECK_FUNC(_NSGetEnviron, [AC_DEFINE(HAVE_NSGETENVIRON, 1, [Define if your system needs _NSGetEnviron to set up the environment])])