Problem with plugin

Hi,
I have a problem with plugin. After activation and settings my WP site does not work. There is problem:

Warning: preg_replace() [function.preg-replace]: Delimiter must not be alphanumeric or backslash in /domains1/pu238500/public/www_root/wp-content/plugins/zalomeni/zalomeni.php on line 124

Thank you for your support.
Miloslav

http://ww.wp.xz.cn/extend/plugins/zalomeni/