diff --git a/m4/sense_api_opts.m4 b/m4/sense_api_opts.m4
index 6ca08ba..79dadfd 100644
--- a/m4/sense_api_opts.m4
+++ b/m4/sense_api_opts.m4
@@ -5,7 +5,7 @@ AC_ARG_ENABLE([senseapi-xcbxorg],
         [Enable XCB/Xorg SenseAPI backend])],
     [AS_CASE([$enableval],
         [no], [enable_senseapi_xcbxorg=no],
-        [yes|*], [
+        [yes|""|*], [
             enable_senseapi_xcbxorg=yes
             AC_DEFINE([XCBXORG_ENABLED], [1],
                 [Define to 1 if you have XCB/Xorg SenseAPI backend])