1Try this in your .htaccess:
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3ErrorDocument 404 http://jobguide.australianenglishcenter.com/404/
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5RewriteEngine On
6RewriteBase /
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8RewriteCond %{REQUEST_URI} ^/404/$
9RewriteRule ^(.*)$ <YourRelativePathToPHPFile>/404.php [L]
10Here,The ErrorDocument redirects all 404s to a specific URL
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12The Rewrite rules map that URL to your actual 404.php script. The RewriteCond regular expressions can be made more generic if you want, but I think you have to explicitly define all ErrorDocument codes you want to override.
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14NOTE: Replace