If your server has mod_perl 2 installed on it (this is for use with apache 2) you will find you have ModPerl::RegistryLoader somehwere on your disk. If it has mod_perl 1 on it (and apache 1) you will find Apache::RegistryLoader. You will definitely find one or the other, unless someone has gone to the trouble to manually delete it. There is no option to NOT install it when installing mod_perl.