nf_conntrack_sip and ekiga

What is the status of ekiga and the nf_conntrack-sip netfilter module?

I saw this bug:
 https://bugzilla.netfilter.org/show_bug.cgi?id=522
from several years ago which suggested that it may work with ekiga now.

I am setting up a router with openWRT which does not seem to have the
conntrack_sip module compiled by default, which makes me a little
suspicious.

I have several sip devices behind the firewall and need to open the
firewall dynamically for sip traffic. And I distinguish the different
clients by using distinct destination ports in the 506* range. If the
nf_conntrack_sip and nf_nat_sip modules work, then presumably they are
all I need. I find netfilter documentation to be dated and inadequate:
it is unclear to me where to find information: as far as I can see, I
have to read the kernel source and the configuration files to get
up to date information.

From 
# modinfo nf_conntrack_sip
...
parm:           ports:port numbers of SIP servers (array of ushort)
...

it looks as if I need to load with the port range. I am not even sure 
whether this is for servers or clients behind the firewall (or both).

Has anyone any experience or suggestions?

ael