Index: src/wp-admin/options-writing.php
===================================================================
--- src/wp-admin/options-writing.php	(revision 40354)
+++ src/wp-admin/options-writing.php	(working copy)
@@ -127,19 +127,19 @@
 <table class="form-table">
 <tr>
 <th scope="row"><label for="mailserver_url"><?php _e('Mail Server') ?></label></th>
-<td><input name="mailserver_url" type="text" id="mailserver_url" value="<?php form_option('mailserver_url'); ?>" class="regular-text code" />
+<td><input name="mailserver_url" required type="text" id="mailserver_url" value="<?php form_option('mailserver_url'); ?>" class="regular-text code" />
 <label for="mailserver_port"><?php _e('Port') ?></label>
-<input name="mailserver_port" type="text" id="mailserver_port" value="<?php form_option('mailserver_port'); ?>" class="small-text" />
+<input name="mailserver_port" required type="number" id="mailserver_port" value="<?php form_option('mailserver_port'); ?>" class="small-text" />
 </td>
 </tr>
 <tr>
 <th scope="row"><label for="mailserver_login"><?php _e('Login Name') ?></label></th>
-<td><input name="mailserver_login" type="text" id="mailserver_login" value="<?php form_option('mailserver_login'); ?>" class="regular-text ltr" /></td>
+<td><input name="mailserver_login" required type="email" id="mailserver_login" value="<?php form_option('mailserver_login'); ?>" class="regular-text ltr" /></td>
 </tr>
 <tr>
 <th scope="row"><label for="mailserver_pass"><?php _e('Password') ?></label></th>
 <td>
-<input name="mailserver_pass" type="text" id="mailserver_pass" value="<?php form_option('mailserver_pass'); ?>" class="regular-text ltr" />
+<input name="mailserver_pass" required type="password" id="mailserver_pass" value="<?php form_option('mailserver_pass'); ?>" class="regular-text ltr" /> 
 </td>
 </tr>
 <tr>