diff --git a/res/pjproject/pjlib/include/pj/config_site.h b/res/pjproject/pjlib/include/pj/config_site.h
index bb590a3e48..65dc1d210f 100644
--- a/res/pjproject/pjlib/include/pj/config_site.h
+++ b/res/pjproject/pjlib/include/pj/config_site.h
@@ -19,6 +19,7 @@
  *   Windows Mobile, useful for testing purposes only.
  */
 
+#define PJ_HAS_IPV6 1
 
 /*
  * Typical configuration for WinCE target.