[Users] no authorize with ATA and phones

[Jens Carl]

Hello list,

i have following code in my openser configuration to prevent that
everybody can make calls to PSTN:

process INVITE messages
-- snip

if( !allow_trusted() ) {
  if( !proxy_authorize( "myrealm", "subscriber" ) ) {
    proxy_challenge( "realm", "1" );
    return;
  } else if ( !check_from() ) {
    sl_send_reply( "403", "Use From=ID" );
    return;
  };
  consume_credentials();
};

-- snap

This works fine with snom200, snom360 and some other phones/ATA.
It isn't working with Linksys IPPhone SPA941, snom100 and the ATA
Linksys SPA 2001.

All these three devices aren't sending the credentials after they are
challenge to send them. I know this because the new INVITE message have
no digest information in it, the call isn't be placed and the following
error message from the logs of OpenSER:

/sbin/openser[3323]: find_credentials(): Error while parsing headers

I have also tried that the second parameter of proxy_challenge are 0
(zero) but that didn't helped.

Have anybody a clue where I can change this behaviour of the three
devices? Have I change some settings, etc of the phones/ATA?

Or maybe I have to change my code for the OpenSER? But I will avoid this
because I don't want to be an open relay.

Thanks in advance

Jens