HI,
I am sorry to post a question to your question, but it seems like you have solved the problem i am having in this post http://forum.pfsense.org/index.php/topic,59670.0.html (i cant figure out how to make load balance work from external network, or internal network at all)
i might be able to help you with your problem:
i had the same problem with not being able to access my webservers on the external domain name when i was on the internal network with the client, i UNticket the following option in System -> Advanced -> Firewall / Nat -> "Disable NAT Reflection for port forwards"
This box should be unchecked, and it should solve your problem (Did for me).
I can post a screenshot of it, if my description is hard to understand (my english is not perfect) :-)
Now, can you help me with my problem ?