[Serusers] connecting two sites

hi guys/gals, I have two ser sites serving two different domains and I want to let them see each other. Earlier this week, someone on this list said that no special config had to be done to get this done, but I am having problems. Both the ser servers are on machines behind the firewalls for security. I have forwarded UDP ports 5060-5070 through to the ser servers. I can see people online going one way, but not the other. The site that can, is able to send messages to the other site and get a response back, but not vice versa. What firewall/forwarding config do I need? cheers, this really has me stumped :) ------------------------------------------------- This service is provided by 3d Computers Ltd. www.3d-computers.co.uk sales(a)3d-computers.co.uk