1. Make a backup of your entire webcp directory.
2. Save a copy your include.httpd, include.named and config.php files
3. Extract webcp-0.5.x.tar.gz and overwrite your webcp directory.
4. Replace include.httpd, include.named and config.php with your saved copies.

Notice: "unserialize() [<a href='function.unserialize'>function.unserialize</a>]: Error at offset 374 of 378 bytes" (...repeated 2 times)