Javascript calendar for rails 2.x

can somebody recommend a js based calendar-select-date-and-time application.
i just need it in a form where the visitor can select several dates.
i should work with the shipped prototype libs with rails 2.0.2.

Thanx

Something like this:

http://agilewebdevelopment.com/plugins/unobtrusive_javascript_date_picker

Best regards

Peter De Berdt

Bingo! That's exactly what I'am looking for!
Thanx.