I am using mod_perl version 1.9. The exact version is 1.99921. I am running a script under PerlRun. This is what my conf file looks like:

 <Location /perl>
     SetHandler perl-script
     PerlResponseHandler ModPerl::PerlRun
     PerlOptions +ParseHeaders
     Options +ExecCGI
  </Location>
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So the script is running under /perl. The first time the script executes, everything is fine. But the next time, a header is not sent and there is an internal server error.

I am using the header function from CGI.pm. What I am doing is this in a base class:

use CGI qw(header);

my $html = defined($ENV{'SERVER_SOFTWARE'}) ? header : '';

# More stuff gets added to $html before it prints to STDOUT
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Why is the header sent the first time and not the next?

Thanks monks.