Router problem

I posted a thread called “Can’t dial out”

I have since figured out my problem, but am not sure how to by pass the issue. here is my set up.

I have a Linux Router/Bridge, 2 nics both in the bridge, then an ADSL connection. I have 2 public static IPs on this system and one private. I am using the private for nat. The 2 IPs have the same first quads, but the next are xx.xx.190.155, and xx.xx.188.49 I also have a /30 subnet and my asterisk box is on .50, router is on .49. When I make out going calls to my peer they originate from my .155 (the main IP) not .50 which is where the peer is expecting them to come from. Now some times it works, but it so random I had no idea it was a router issue, until now. If I add a new peer and add on of my DIDs to expect calls from .155 it works with no problems. Now I was under the impress that Linux bridging was transparent, if it is would my NAT/tables interfere with this?

Hope this is not too confusing.

Also on the asterisk box the calls appear to be calling out on the private IP address. Is there a way to force dialing via the public IP.