asterisk users - May 2005 - snom190 and SUBSCRIBE failures with 407

Hi,

I have searched and searched, but cannot identify what is happening here...

I have several snom190 phones, and all of them have the 5th function
key set to call "asterisk" by using the "destination"
option. This
automatically causes the phone to SUBSCRIBE for NOTIFY messages for
the "asterisk" destimation.

Asterisk does not seem to like the SUBSCRIBE requests. It logs the message:

NOTICE[22527]: chan_sip.c:7601 handle_request: Failed to authenticate
user <sip:681@pabx2.bp.rpanetwork.net>;tag=blw952f4zl for SUBSCRIBE

Or similar for every subscribe... The phone is registered happily, and
can make and receive calls. I have set up a "hint" for the
"s"
extension, although I do not think this should be necessary.

I checked the SIP packets, and Asterisk is responding with "SIP
Status: 407 Proxy Authentication Required", but if I look at the
request, all of the authentication data was provided (in md5 format)
in the original SUBSCRIBE request.

Any clues out there? This is causing really annoying messages on the
snom phone's screen as it thinks it needs a password entering.

Thanks.
Steve