If I run your script from the commandline I get:

Content-type: text/html

<h1>Software error:</h1>
<pre>Global symbol &quot;$var&quot; requires explicit package name at 
+/home/emile/tmp/aap.pl line 13.
Global symbol &quot;$var&quot; requires explicit package name at /home
+/emile/tmp/aap.pl line 14.
Execution of /home/emile/tmp/aap.pl aborted due to compilation errors.
</pre>
<p>
For help, please send mail to this site's webmaster, giving this error
+ message 
and the time and date of the error.

</p>
[download]

Which makes me pretty sure the fatals/warnings are processed as if they'd go to a browser. My guess is that you are using some form of cached web-environment (mod_perl-ish maybe?). What happens if you restart your webserver?