With the increase of multimedia content on the WWW, multimodal presentations using interactive lifelike agents become an attractive style to deliver information. However, for many people it is not easy to write multimodal presentations. This is because of the complexity of describing various behaviors of character agents based on a particular character system with individual (often low-level) description languages. In order to overcome this complexity and to allow many people to write attractive multimodal presentations easily, MPML (Multimodal Presentation Markup Language) has been developed to provide a medium-level description language commonly applicable to many character systems. In this paper, we present a new emotion function attached to MPML. With this function, we are able to express emotion-rich behaviors of character agents in MPML. Some multimodal presentation content is produced in the new version of MPML to show the effectiveness of the new emotion expression function.