[SR-Users] How to get Destination port UDP

[andrzej.ciupek-asterisk.edu.pl]

Hello

I am using Kamailio to collect data about active calls. I write INVITEs 
to database, and delete it on BYE or any REL.
I would like to write source and destination port too, but don't know 
how to get destination port.
I have tried variables:

$dp, $rp, $Rp, $op

But when I don't have port in URI like INVITE IP:PORT, $rp have default 
value of 5060.

I would like to get real UDP port, that INVITE does to. Is it possible 
using PSEUDO VARIABLES?

Greetings
Andrzej