> Is there any conditions in which the open files limit will be
> reduced (switching users to nobody for example, or forking a child)?
> There are no setrlimits inside of apache that lower the file
> limit. Is there any other condition other than the resource limit
> that socket will return too many open files?

Could be you're hitting FD_SETSIZE?  See /usr/include/sys/types.h.

This has to be limited by the software though, it isn't a system
error to exceed FD_SETSIZE....

Dave.