[Plugin: Search Regex] Class 'stripslashes' not found

When I try to run a search with the Search Regex plugin, I get this error:

Fatal error: Class ‘stripslashes’ not found in /home/www/www/testing/wp-content/plugins/search-regex/search-regex.php on line 51

Any ideas what is wrong and how to fix?

http://wordpress.org/extend/plugins/search-regex/