Is the "X-Mailer: PHP/<phpversion>" header required to send a mail in PHP?
<p>A lot of examples I found online about sending emails with php set the header</p>

<pre><code>"X-Mailer: PHP/" . phpversion()
</code></pre>

<p>But I find disclosing I'm using php and its version a very bad security practice.</p>

<p>Is this a required header?</p>
