<directivesynopsis>
<name>SSLEngine</name>
<description>SSL Engine Operation Switch</description>
-<syntax>SSLEngine on|off|optional</syntax>
+<syntax>SSLEngine on|off</syntax>
<default>SSLEngine off</default>
<contextlist><context>server config</context>
<context>virtual host</context></contextlist>
+<compatibility>
+ Support for the "optional" argument was removed in 2.4.64. It enabled
+ RFC 2817 (TLS Upgrade) support.
+</compatibility>
+
<usage>
<p>
</VirtualHost>
</highlight>
</example>
-<p>In Apache 2.1 and later, <directive>SSLEngine</directive> can be set to
-<code>optional</code>. This enables support for
-<a href="http://www.ietf.org/rfc/rfc2817.txt">RFC 2817</a>, Upgrading to TLS
-Within HTTP/1.1. At this time no web browsers support RFC 2817.</p>
</usage>
</directivesynopsis>