+#### D-Bus support (optional) ####
+
+AC_ARG_ENABLE([dbus],
+ AS_HELP_STRING([--disable-dbus],[Disable optional D-Bus support]))
+
+AS_IF([test "x$enable_dbus" != "xno"],
+ [PKG_CHECK_MODULES(DBUS, [ dbus-1 >= 1.0.0 ], HAVE_DBUS=1, HAVE_DBUS=0)],
+ HAVE_DBUS=0)
+
+AS_IF([test "x$enable_dbus" = "xyes" && test "x$HAVE_DBUS" = "x0"],
+ [AC_MSG_ERROR([*** D-Bus support not found])])
+
+AS_IF([test "x$HAVE_DBUS" = "x1"],
+ [
+ save_CFLAGS="$CFLAGS"; CFLAGS="$CFLAGS $DBUS_CFLAGS"
+ save_LIBS="$LIBS"; LIBS="$LIBS $DBUS_LIBS"
+ AC_CHECK_FUNCS(dbus_watch_get_unix_fd)
+ CFLAGS="$save_CFLAGS"
+ LIBS="$save_LIBS"
+ ])
+
+AC_SUBST(DBUS_CFLAGS)
+AC_SUBST(DBUS_LIBS)
+AC_SUBST(HAVE_DBUS)
+AM_CONDITIONAL([HAVE_DBUS], [test "x$HAVE_DBUS" = x1])
+AS_IF([test "x$HAVE_DBUS" = "x1"], AC_DEFINE([HAVE_DBUS], 1, [Have D-Bus.]))
+
+PA_MACHINE_ID="${localstatedir}/lib/dbus/machine-id"
+AX_DEFINE_DIR(PA_MACHINE_ID, PA_MACHINE_ID, [D-Bus machine-id file])
+
+#### HAL support (optional), dependant on D-Bus ####