Linking to ICE-9232. The on* events aren't supported/rendered. They appear in the TLD documentation because ace:comboBox extends from h:inputText, which supports them. The same situation is present in ace:autoCompleteEntry. Once ICE-9232 is solved, the on* events will be removed from the TLD documentation of these components.

It is not the design intent to support the "onxxx" passthrough eventhandler attributes on the ACE components. The reason that these appear in the TLD is that the ACE generator currently cannot block them from being included due to inheritance. This will be corrected via the generator improvement noted in ICE-9232.

The justification for not supporting the "onxxx" passthrough attributes is that they cannot be readily applied consistently to all ACE components, as many use complex states and multiple elements for rendering, and thus the "onxxx" events would not be applicable in many cases. Instead, the intention is to implement as necessary client events in the components (accessed via the ace:ajax tag) to support those component events that are useful/required.