Special characters other than spaces are replaced with their UTF-8 value in hex, each byte preceeded by a '%':
'+' becomes '%2B',
'%' becomes '%25',
etc.

$cgi->param() and $cgi->params() will properly unescape everything for you.

In reply to Re: Encoding spaces in CGI form data by ikegami
in thread Encoding spaces in CGI form data by fepifanio

Title:
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