Small errorscript to generate informative content on your errorpages, seeks through section 10 of rfc 2616 to find matching description for the error; To install and use put it in you httpd.conf or .htaccess as such:

ErrorDocument 401 /error.pl
ErrorDocument 402 /error.pl
ErrorDocument 403 /error.pl
...
ErrorDocument 500 /error.pl
ErrorDocument 501 /error.pl
ErrorDocument 502 /error.pl
...

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