if taint checking is on your script will abort

Actually it won't. Taint looks to see if you do dangerous things with external vars. Printing is not dangerous. Invalid HTML will never cause a 500 error BTW.

[root@devel3 root]# cat test.pl
#!/usr/bin/perl -wT
use strict;
use CGI;
my $q = new CGI;
print $q->header();
my $ct = $q->param('ct');
print $ct;
[root@devel3 root]# ./test.pl ct=foo%0A
Content-Type: text/html; charset=ISO-8859-1

foo
[root@devel3 root]#
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