CGI.pm handles custom HTML tags just fine. You need to add the custom tag names to the list of function names imported from the module and it will synthesis functions for the new tags.

use CGI qw(:standard myscriptname);

print myscriptname({type => 'type_of_field',
                    value=> 'list,of,values'});
[download]

This prints

<myscriptname value="list, of, values" type="type" /> --
<http://www.dave.org.uk>

"The first rule of Perl club is you do not talk about Perl club."
-- Chip Salzenberg