I found another component to the seg fault. I am using a dynamically linked mod_deflate output filter as well (will test with static). I get no seg fault when I comment out the DEFLATE line in the Apache config. (Sorry, I hadn't noticed this piece of the puzzle.)
LoadModule deflate_module /opt/apache2/modules/mod_deflate.so
...
<Location /prog >
SetHandler perl-script
PerlResponseHandler ModPerl::Registry
Options ExecCGI
AddOutputFilterByType DEFLATE text/html text/plain text/xml
</Location>
