ucFilterPopup is called before rendering the values in Popup list fields and allows the list of values to be modified.
Field Rendering Methods
public void ucFilterPopup(SesameSession session, // current session
ValidationList selList, // the items to be displayed
String pGlobal, // ddname
HashMap selectedVals, // selected values in the list
HashMap attributes, // attributes of the list
String mode, // where it's called from...
String layoutType);