You may want to have a look at what version of the CGI::Carp module you are using. There is indeed a bug in a fairly recent version that caused fatalsToBrowser to fail.

After I had verified that it was indeed the module and not my own incompetence (with the help of a monk here) I submitted the bug to Lincoln Stein who acknowledged it. I'm not sure if it was fixed in the latest release (3.0) but the last 2.xx release was a culprit.

I downgraded one release at at time until I had a working version. I arrived at this when I installed CGI.pm 2.93 using CPAN.pm which includes CGI::Carp 1.20.

To check your versions you can run this code quickly:

#!/usr/bin/perl
use CGI;
use CGI::Carp;

print "carp .. $CGI::Carp::VERSION\ncgi .. $CGI::VERSION\n\n";
[download]

Good luck. :)