APPLICATION ERROR #18

[x55a]

Hi!

I need some help. How can I modify mantis?

config_defaults_inc.php
$g_webmaster_email = 'name@domain.name';

New value:
$g_webmaster_email = 'name2@domain.name';

When i do modify this value (or anything anywhere in code) i get an error message:

APPLICATION ERROR #18
Page redirection error, ensure that there are no spaces outside the PHP block (<?php ?>) in config_inc.php or custom_*.php files.

If I modified an php file. I get this message. I cant understand what is the wrong. When I do back copy old file the mantis is ok without error message.

Please help me!!!

Mihaly [x55a]