diff --git a/server/ref/index.php b/server/ref/index.php
index 6f69f82..91c7c88 100755
--- a/server/ref/index.php
+++ b/server/ref/index.php
@@ -39,7 +39,7 @@ $res = "";
 
 $statement = $db->prepare("SELECT password FROM gpass WHERE login=:login");
 
-echo "protocol=$PROTOCOL_VERSION\n";
+echo "protocol=gpass-$PROTOCOL_VERSION\n";
 
 for ($i=0; isset($_POST["k$i"]); $i++)
 {