Serial Review in Visual Annotate

System

I am using Visual Annotate using one of the configurable workflows in 6.1. It works fine when I add one person as a reviewer. Does any body know how to add multipeople in the review process. I have tried chaging this review_type=grouptask[group:demomaster,user:jsmith] in the cfg file., but it gives me an error. Has anyone know hoe to configure serial review for more than one people using VA.