- added confirmation to removing bbcodes

- added optional MX and DNSBL checks
- added backtrace (triggering sql error) on error within sql_in_set as well as making sure it is handling an array
- let users having f_list access to a forum actually see the forum without a topic list and not displaying an error message - this allows for giving people access to subforums but not the parent forum without the need to add the (sub-)forum to the index.
- some additional bugfixes


git-svn-id: file:///svn/phpbb/trunk@6414 89ea8834-ac86-4346-8a33-228a782c2dd0

phpBB/includes/functions_user.php

@@ -1216,6 +1216,18 @@ function validate_email($email)
 		return 'EMAIL_INVALID';
 	}
 
+	// Check MX record.
+	// The idea for this is from reading the UseBB blog/announcement. :)
+	if ($config['email_check_mx'])
+	{
+		list(, $domain) = explode('@', $email);
+
+		if (phpbb_checkdnsrr($domain, 'MX') === false)
+		{
+			return 'DOMAIN_NO_MX_RECORD';
+		}
+	}
+
 	if ($user->check_ban(false, false, $email, true) == true)
 	{
 		return 'EMAIL_BANNED';