[Serusers] kphone needs to register twice

[Juha Heinanen]

Jiri Kuthan writes:

 > keeping callid is legal and desirable for REGISTER requests. REGISTER
 > with 0 means unREGISTER, no clue why k-phone sends it...

when kphone is registered with the proxy and the user presses unregister
button, kphone sends register message with expire=0.  that causes
unregister button to turn into register button.  when the user then
presses register button, kphone sends a register message with
expire=configured value. 

i dont see any problem with that behavior.

-- juha