diff --git a/en_US.ISO8859-1/books/faq/book.sgml b/en_US.ISO8859-1/books/faq/book.sgml
index c513d5faa4..101f5def11 100644
--- a/en_US.ISO8859-1/books/faq/book.sgml
+++ b/en_US.ISO8859-1/books/faq/book.sgml
@@ -6333,7 +6333,7 @@ if-bus.UUCP                   uucp-dom:if-bus
           <para>Final hint: if you are uncertain whether some particular
             mail routing would work, remember the <option>-bt</option>
             option to sendmail. It starts sendmail in <emphasis>address
-            test mode</emphasis>; simply enter <literal>0</literal>,
+            test mode</emphasis>; simply enter <literal>3,0</literal>,
             followed by the address you wish to test for the mail routing.
             The last line tells you the used internal mail agent, the
             destination host this agent will be called with, and the