diff --git a/Doc/Sdi/mail.xml b/Doc/Sdi/mail.xml
index d671079135496c38434e15d15bb991a46b82c7f7..387821ef079687c8f993ae36fab8cd5d036070bf 100644
--- a/Doc/Sdi/mail.xml
+++ b/Doc/Sdi/mail.xml
@@ -133,8 +133,8 @@
 
       <itemizedlist>
         <listitem>
-          <para>check that postfix is running; try to connect via
-          telnet</para>
+          <para>check that postfix is running; try to connect via telnet
+          (telnet localhost 25)</para>
         </listitem>
 
         <listitem>
@@ -170,8 +170,9 @@
 
           <itemizedlist>
             <listitem>
-              <para>meaning use telnet on your local host system to sdiXb and
-              send a mail to a user on sdXa</para>
+              <para>meaning use telnet on your local host system (the pc in
+              front of you, not a vm) to sdiXb and send a mail to a user on
+              sdXa</para>
             </listitem>
 
             <listitem>
@@ -201,7 +202,7 @@
 
             <listitem>
               <para>then bind your <acronym>sasl</acronym> authentication to
-              your existing <xref linkend="glo_LDAP"/>.</para>
+              your existing <xref linkend="glo_LDAP"/>. (optional)</para>
             </listitem>
           </itemizedlist>
         </listitem>
@@ -219,9 +220,9 @@
         </listitem>
 
         <listitem>
-          <para>add an fantasy domain to your <xref linkend="glo_DNS"/> Setup
-          and let its <acronym>mx</acronym> record point to your mail
-          server</para>
+          <para>add an fantasy domain (e.g. supertollermistudent.de) to your
+          <xref linkend="glo_DNS"/> Setup and let its <acronym>mx</acronym>
+          record point to your mail server</para>
         </listitem>
 
         <listitem>
@@ -249,7 +250,8 @@
               <tip>
                 <para>Read about <command
                 xlink:href="http://linux.die.net/man/1/postmap">postmap</command>
-                and set your local resolver to your own DNS</para>
+                and set your local resolver (resolv.conf) to your own
+                DNS</para>
               </tip>
             </listitem>
           </itemizedlist>
@@ -289,15 +291,21 @@
 
         <listitem>
           <para>both connections should be secured via <xref
-          linkend="glo_TLS"/>.</para>
+          linkend="glo_TLS"/>. Look in your mail.log to verify this </para>
         </listitem>
       </itemizedlist>
     </section>
 
     <section xml:id="sdiSectSpamVirusDefense">
-      <title>Spam and Virus defense</title>
+      <title>Spam and Virus defense (optional)</title>
 
       <para><itemizedlist>
+          <listitem>
+            <para>Because we have not enough time this is optional. If you
+            want your own mailserver someday you should do all those
+            things</para>
+          </listitem>
+
           <listitem>
             <para>Now we will use the smtpd_*_restrictions in the
             <filename>main.cf</filename>. This are one key element to make
@@ -412,7 +420,7 @@
       </section>
 
       <section xml:id="sdiSectSpf">
-        <title><acronym>SPF</acronym> (optional)</title>
+        <title><acronym>SPF</acronym></title>
 
         <para>Where are plenty of Spam prevention techniques like
         <acronym>DMARC</acronym>, <acronym>DKIM</acronym>,