Control which widgets appear by page or category with Atahualpa Theme

I am using the Atahualpa Theme, and I have a left and right sidebar. I want widgets contained in those sidebars to appear on certain pages and other widgets to apear on other pages. Can I control this. I am aware that I can make sidebars disappear on pages, but that is not what I need. I want to control when widgets appear in a sidebar based on the page or category