I'm trying to configure WCCP forwarding of HTTPS traffic with a multicast group. The group-listen configuration option doesn't seem to be taking effect for numeric service_ids. To eliminate problems with the web-caches I tried ping-testing, and the routers respond on any address configured with web-cache, but none configured with any numeric service ID. I've searched the support pages and release notes, but have found no mention of this behavior for our test routers (800 series running 12.4(22)YB) or any other router/IOS combination.
ip wccp web-cache group-address 126.96.36.199 password password
ip wccp 70 group-address 188.8.131.52 password password
In the above configuration pings to 184.108.40.206 are responded to by the router's unicast address, where pings to 220.127.116.11 are not responded to at all. WCCP in all-unicast mode works with HTTP and HTTPS, and with HTTP in multicast. I can update the router's firmware if this will help, but since there is no mention of this issue in any documentation I don't want to just randomly mess with my firmware in hope of a solution. Has anyone seen this behavior before? Found a solution?