yes, it works fine under ESX 3.0.1 at least for the smaller license versions -- I'm not sure how well it would scale though for 50+ managed devices and you have to pay careful attention to security/high availability of the virtual machine. My understanding is that Cisco hasnt given any indication that vmware would be a supported environment for CSM.
I've had CSM 3.0.1 give me a lot of headaches and error messages running under VMware, but CSM 3.1 and 3.1.1 run fine. I'm running the free VMware on Windows 2003 server. CSM works well with a few devices even if you limit the guest OS memory to under a meg.
We have configured the outside and inside Interface with official ipv6 adresses, set a default route on outside Interface to our router, we also have definied a rule , which also gets hits, to permit tcp from inside Interface to any6.
In Syslog I also se...