[Users] redirect and proxy functionality

I have a clash of concepts in my head, and it's messing with my openser config. 1) On one hand I think that if a phone is configured to use an outbound proxy then it should use it. Period. 2) On the other hand, I now do a "300 Redirect" and the phone sends back, to the same box, the same Invite but with the redirected r-uri. This is consistent with 1), but in this case I don't want this behaviour... If things are supposed to work like 2) then why wouldn't I just rewritehostport() and t_relay it without bothering with the redirect? In any case, I don't want to do that (rewritehostport), I want the redirect to be "try over there, and don't bug me again." I don't want to relay the dialog. So, in the real world, what should I hope to get out of a redirect (3xx) code? Thanks, -mark