[Serusers] kphone needs to register twice

Hello, I experienced some strange behaviour of my kphone (V3.11). When I click on register the first time nothing happens (no error message, keeps offline). Clicking the "register" button the second time makes kphone go online. With the help of Uli and Daniel (thanks !) I could record the network traffic caused by both clicks. In the attached file the first two messages were caused by the first (unsuccessful) click on "register". The next two messages where caught after my second click on register which succeeds. Comparing the two requests I saw the different entries in the "Expires" field (fist 0, second 900) but to my surprise even the call-IDs are the same. Do you know what is going wrong here ? BTW: Of course I don't mind to click on register twice in kphone. But right now I have a problem receiving messages with MS Messenger (will describe that separately if I cannot solve it myself) and I'm trying to find out if the reason is within the SER on UA's side. Therefore I cannot ignore anything that looks like an error (e.g. wrong config) in SER or an UA while I'm testing different scenarios. Thanks, Alex