'Premature end of script headers' usually means you didn't send the correct headers to display the output in your web browser. Make sure before you print anything out that you have a line that looks like this:

print "Content-type: text/html\n\n";
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Alternatively if you are using the CGI module you can use it to print your header:

print $cgi->header(); # defaults to text/html
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Hope that helps
Chris