[Serusers] click2dial issue

[hiSIPatH]

Hi all,

i am trying to use click 2 dial in phonebook (serweb). But
unfortunately i am not able to get this to work. I always get the
following error in the popup window:

407 Proxy Authentication Required

The sip trace gives the following ( i have sniffed eth0 and lo)

on the eth0 (with public ip@ the dns query and response)

No.     Time        Source                Destination           Protocol Info
     16 3.618415    89.xxx.xxx.218        89.xxx.xxx.129        DNS
  Standard query SRV _sip._udp.yyyy.zzz


No.     Time        Source                Destination           Protocol Info
     17 3.618868    89.xxx.xxx.129        89.xxx.xxx.218        DNS
  Standard query response SRV 200 0 5060 proxy.yyyy.zzz

on my loopback interface

No.     Time        Source                Destination           Protocol Info
      1 0.000000    89.xxx.xxx.218        89.xxx.xxx.218
SIP/SDP  Request: INVITE sip:firstname.lastname at yyyy.zzz, with session
description
No.     Time        Source                Destination           Protocol Info
      2 0.000251    89.xxx.xxx.218        89.xxx.xxx.218        SIP
  Status: 407 Proxy Authentication Required
No.     Time        Source                Destination           Protocol Info
      3 0.000332    89.xxx.xxx.218        89.xxx.xxx.218        SIP
  Request: ACK sip:firstname.lastname at yyyy.zzz

i can see several INVITE-407-ACK but no INVITE with
proxy-authorization from controller at yyyy.zzz

have i forgotten to configure something.
thx in advance