McAfee has two interesting offerings for Virtualization within the System Security Suite, albeit this probably doesn't address your need for "policy fine funing." In general, you will want to keep your On-Access policies pretty locked down as the system's will operate as if they were physical for On-Access protection.
The following are the links to these products:
McAfee's also partnered Catbird that has some interesting virtual security technology.
Team McAfee at Ciphent