Adding a Calendar

I am trying to add the calendar seen here: http://www.dynarch.com/projects/calendar/
to a tab. I am using absolute positioning. I have created a new AW.HTML.DIV and I have specified this DIV as the parent for the calendar, but everytime I load the page, I get the error:

"Calendar.setup: Flat specified but can't find parent."

I realize that this is coming from the calendar code and not AW code, but I can't seem to figure out how to add any widgets outside of the AW toolkit in and get it to play with AW widgets.

I've tried refresh(). Any ideas would be greatly appreciated.