asterisk users - Aug 2005 - How to configure Outbound Proxy for REGISTER?

Is there no way to configure an outbound proxy when registering? I am
trying to use proxy.siprovider.com as the outbound proxy and
mydomain.com as my fromdomain. However, the fromdomain only seems to
take effect for INVITEs, not for REGISTERs. 


I have the following configuration: 

[general] 
port = 5060 ; Port to bind to 
bindaddr = 10.0.1.1 ; Address to bind SIP channel to 
context = sip-external ; Default context for incoming calls 
tos=reliability ; IP QoS parameter, either keyword or value 
maxexpirey=180 ; Max length of incoming registration we allow 
defaultexpirey=160 ; Default length of incoming/outoing registration 
disallow=all ; Disallow all codecs 
allow=ulaw ; Allow codecs in order of preference 


register => myname:mypassword@mysipprovider.com 

[mysipprovider.com] 
type=peer 
insecure=yes 
insecure=very 
host=proxy.sipprovider.com 
fromdomain=mydomain.com 
username=myname 
secret=mypassword 
canreinvite=no 

The REGISTER looks like: 

REGISTER sip:mydomain.com 
Via: ... 
From: <sip:myname@proxy.sipprovider.com>:tag=... 
To: <sip:myname@proxy.sipprovider.com> 
.. 

I want the REGISTER to look like: 

REGISTER sip:mydomain.com 
Via: ... 
From: <sip:myname@mydomain.com>:tag=... 
To: <sip:myname@mydomain.com> 
.. 

Any insight would be greatly appreciated. 

Thanks, Michael