Interoperability issues for a 6500 Cisco switch and a 3Comm 7700

I have a 6500 series Cisco switch at the core. I want to include a 3Com 7700 series switch for resiliency at the core layer. Can you tell me the interoperability issues that may arise including VRRP interoperability?

Though they are similar, there are differences too -- like the multicast address being used, and the preempt command. As far as interoperability is concerned, I do not see any known issue as VRRP has of late being used by most of the vendors including Cisco.

My suggestion would be to check and know what you are doing before putting the boxes in production.