Multicast through Checkpoint FW?

We're working on lighting up multicast throughout our network. Getting MBGP routes correctly from my ISP and things are working well on our border router and switches. However, we're having some issues getting mcast through our Checkpoint firewall to our core router. Cisco's pitched putting a GRE tunnel between our border router and the core router to circumvent the FW, etc., etc., which just seems so clunky. Has anyone found an appropriate method to get multicast to function normally without resorting to GRE methods? thanks for any info! roah