SIP Phone Login and Registration

[thargi]

CM 6.0.1
ASM and SMGR 6.3

I am trying to set up an Avaya 9641g SIP phone in my environment. I have set the firmware on the phone to be SIP. I have set up the user profile and the communication profile in SMGR, and verified that the extension (8700) shows up in CM.
When I boot the phone, it goes through its bootup process, receives an IP from DHCP, and gets to the Enter username field. I dial 8700 and press enter. I get the Enter password field. I dial 8700 (the security code in CM endpoint profile) and press enter. Then I get "Request not allowed (403)" and a field with a blinking cursor. What is that all about?
Is the username field not wanting the extension and the password field not wanting the security code? If not, what is it looking for? Avaya's documentation on this is not good at all.
How do I get this SIP phone logged in and registered?

Thanks