Application Mapping with IP Networks

VoIP uses a large range of ports. I want to tag those ports coming to/from a specific network range as VoIP from that area. The problem is, the defined ranges talk to each other, natually. An IP in one range talks to an IP in another range during a phone call.

For example:

Ports 10000 - 20000
IP Network: 10.10.10.0/24
Application: VoIP Main Office

Ports 10000 - 20000
IP Network 20.20.20.0/24
Application: VoIP Extension Office

Ports 10000 - 20000
Application: VoIP (Generic)

How is Netflow Analyzer going to map these applications? I created the first application mapping before the second, so most of the traffic appears to fall into that mapping. Is the application mapping tied to source, destination, both?

I'm also still getting some VoIP traffic showing up in the "VoIP (Generic)" mapping even though one of the IP addresses is from the "Main Office" range.

Thank you for any insight you can give.

---John Holmes...