diff --git a/mod/forum/lib.php b/mod/forum/lib.php
index 0c4243e97a8ee..fc09a346eb3fa 100644
--- a/mod/forum/lib.php
+++ b/mod/forum/lib.php
@@ -43,6 +43,10 @@
     set_config("forum_maxbytes", 512000);  // Default maximum size for all forums
 }
 
+if (!isset($CFG->forum_replytouser)) {
+    set_config("forum_replytouser", true);  // Default maximum size for all forums
+}
+
 
 
 /// STANDARD FUNCTIONS ///////////////////////////////////////////////////////////