I know Revive is a fork of OpenX, and it seems OpenX offers various different custom variable types http://docs.openx.com/ad_server/targeting_custom_variables.html. What interests me the most is list, as I have a variable category which could have multiple values; for example, "cat=dog,fish,rabbit", and I would like to target on "Contains only: dog" or "Contains any of: dog,cat" or even "Contains all of: horse,cow". Is this possible with Revive Adserver?