You are correct that the iPad is enabled with H.460 and works with the VBP ST and CMA 5.4 and above. I did want to let you know that CMAD for Mac version 5.2 (now on the web) also has H.460 and can work with the same combination you have been using with the iPad. Sorry, but I'm not sure what FQDN is.
I'm having the same issue. If the ipad is on my network and registers directly to the CMA server, everything works. If it's outside the network and registers via the VBP-ST, it registers to the CMA but the gatekeeper status is "unknown". I can make calls to other endpoints, but other endpoints cannot call the ipad. It doesn't matter whether the ipad is pointing to the IP address or the VBP or its FQDN.
Is this an issue with the RealPresence Mobile or is there something in the config of the VBP or CMA that needs to be changed?
I was wondering if anyone had a solution to this problem as it seems pretty prevelant. Thanks!