I was having the similar issue as all you guys. Here is what I did

In the wireless router admin page you need to change the firewall settings as motorola blocks port 5100 by default

Click on the firewall settings and select the Firewall policy as “Custom” and click apply.
Now click on the advanced link at the top ( right below the Policy tab), you would see a scrolling window within the page. Scroll down to the bottom of this window and select Policy template as Medium and hit apply ( it would ask you for some confirmation, click Yes )
Now add a New Filter Entry in the same window ( at the very top )
Port Id : Yahoo cam
Enable : Yes
Allowed Protocol: IP
Port Range : 5100 – 5100
Allow Inbound : Yes
Allow Outbound : Yes

Click on Add button.

You are good to go 🙂

Cheers
Hemant