How can I set a category, when using janet.RandomImage within a DNN skin?

The Notes.html states:

The RandomImage module may be added as a user control to a DotNetNuke skin.

<%@ Register TagPrefix="janet" TagName="RandomImage" Src= "~/DesktopModules/janet.RandomImage/RandomImage.ascx" %>

Ensure that a link to the user control has been added at the top of your skin design. <%@ Register TagPrefix="janet" TagName="RandomImage" Src= "~/DesktopModules/janet.RandomImage/RandomImage.ascx" %>Now in the code where you want the link to appear on the skin add a tag definition.

<janet:RandomImage="RandomImage" runat="server" />

Is there something missing??

Thomas