Selectables not working?

Selectables not working?


I have tried this demo in both Firefox 3 and Chrome, and neither one
allows me to "draw a box around the elements" to select them. I am
looking for a rubber-band type selection box, similar to this one:
http://www.nwhite.net/2009/02/09/advanced-ui-component-using-rubberband-and-draggroup/
Any ideas?