diff --git a/inc/CalDAVRequest.php b/inc/CalDAVRequest.php
index 2cb5e039..843dd624 100644
--- a/inc/CalDAVRequest.php
+++ b/inc/CalDAVRequest.php
@@ -610,7 +610,7 @@ class CalDAVRequest
   function DoResponse( $status, $message="", $content_type="text/plain; charset=\"utf-8\"" ) {
     global $session, $c;
     @header( sprintf("HTTP/1.1 %d %s", $status, getStatusMessage($status)) );
-    @header( sprintf("X-RSCDS-Version: RSCDS/%d.%d.%d; DB/%d.%d.%d", $c->code_major, $c->code_minor, $c->code_patch, $c->schema_major, $c->schema_minor, $c->schema_patch) );
+    @header( sprintf("X-DAViCal-Version: DAViCal/%d.%d.%d; DB/%d.%d.%d", $c->code_major, $c->code_minor, $c->code_patch, $c->schema_major, $c->schema_minor, $c->schema_patch) );
     @header( "Content-type: ".$content_type );
     echo $message;