Are you using a single print() under PerlEx? If not, try to use a single one (i.e.: buffer all output in a variable and send in one shot). I remember a buffering issue related to PerlIS in 5.8.x back in 2004/5 and it can only be mitigated with a single call to print. Multiple calls were creating some sort of error. And for the apache issue. I think if you did not compile Apache & mod_perl from source, we can't be sure if there is a problem in Apache setup or your code.