[Zope] Zope and Javascript

Does anyone know of any resources that describe the use of Javascript within Zope? In particular, I am trying to call a Javascript function using the onChange event handler that is tied to a HTML select element. I need this Javascript function to perform an SQL query and then have it populate another HTML select element with the result set. Is this possible within Zope considering that queries are performed by Z SQL methods and possible other factors that I am unaware of? Any help would be greatly appreciated. Thanks. - Asad