1. A method for dynamically generating a vocal help prompt in a multimodal application, the method comprising: detecting a help-triggering event for an input element of a VoiceXML dialog, the detecting implemented with a multimodal application operating on a multimodal device supporting multiple modes of interaction including a voice mode and one or more non-voice modes, the multimodal application operatively coupled to a VoiceXML interpreter, the multimodal application having no static help text; retrieving, by the VoiceXML interpreter from a source of help text, help text for an element of a speech recognition grammar; forming by the VoiceXML interpreter the help text into a vocal help prompt; and presenting by the multimodal application the vocal help prompt through a computer user interface to a user.