The RichFaces scaffold generator creates rich:calendar components in the facelets, but without a datePattern attribute. The behavior of this component in such a case is to not provide the embeddded timepicker. This works for temporal fields of type Date.
But, this is certainly not sufficient for temporal fields of type Timestamp. A datePattern with a time pattern like MMM d, yyyy HH:mm or MMM d, yyyy hh:mm:a needs to be generated for such fields to allow time inputs.
For temporal fields of type Time, consider generating a different widget, since the RichFaces calendar widget is not capable of providing the timepicker alone.