WWW4MAIL implements access control to remote site.

It would allow you to access a site by IP addresses
only when it can successfully get a hostname for
the IP address and the hostname is not listed in the
list of sites to stop.

Also, www4mail will not send a page or access a site
that is listed in it's private Access Control List
in which case you will receive back an Error 403
- Restricted Access Error code.

SEE ALSO
help errors