bind internal domain configuration

[dave]

Hello,
 I hope this is the correct forum for this question, i believe it is bind
that is my problem, though i'm almost certain it's a configuration error on
my part. I've got two domains i'll call them example.com and example.net for
the purposes of this explanation. These domains are available via www from
the net, and are hosted on one of my machines, which is on an internal
network behind a firewall. Now from the net any traffic can get to both
domains. Before i had this arrangement i had internal dns set up which i
called my internal domain example.net. When i go to www.example.net it works
fine, i see that web page and so forth, however when going this is internal,
to www.example.com or make any actions to my .com domain i get timeouts or
404 page not found messages. I'm wondering if i have to change my internal
domain to something different than my two public domains, or if there's
another solution. I'm using bind9 on my internal dns server if that matters.
Thanks.
Dave.